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Is Artex on ceilings and walls a Health Hazard?

Fri, 22 Feb 2019 15:47:39 GMT

'No I won't buy the property as there is Artex on the ceilings!'

Chatting with the director of a local Estate Agency it appears that property buyers have pulled out just because the surveyor has noted ‘Artexed ceilings’.

Is Artex dangerous? If so why?

It’s true that some of the textured plaster finishes used on ceilings and walls contained asbestos.

Asbestos has been known as a potential health hazard since the late 1700’s so it’s nothing new. It can cause a lung disease Mesothelioma, more commonly known as asbestosis.

Who is at risk?

Well it is really ‘luck of the draw’, a bit like smoking. If you worked with asbestos, asbestolux and asbestos lagging you will have been in the high risk category. Working in construction and more recently demolition the risk is very much increased.

The HSE (Health and Safety Executive) provide a lengthy list of the various trades and professions that are at risk on their website: http://www.hse.gov.uk/asbestos/risk.htm

Risk assessment

In comparison with smoking it doesn’t follow that having one cigarette will give you lung cancer. It could though and that is where ‘luck of the drawer’ comes in. As with the case of Roy Castle who was a non-smoker it is possible to contract lung cancer by being in a room with smokers. But it doesn’t mean it is going to happen – just the risks are increased.

Okay but what about the Artex ceilings?

During the 1970’s many new buildings had the then fashionable textured ceilings. Swirly non-descript patterns through to stipple effect with plaster coving around the top of the wall.

As with most fashions plain, smooth white ceilings were ‘old hat’ and could be made to look luxurious and modern with the figured coating. It also covered up cracked ceilings.

To stop the thin coat of plaster drying out too fast and help it bond powdered asbestos known as ‘chystotile asbestos’ was added to the plaster during manufacture. It accounted for less than 2% by volume of the plaster.

Is there a risk to health? Yes is the short answer and that is the reason it was banned on November 24th 1999. Asbestos and materials containing asbestos were banned in 1985 however chrysotile could still be used until it was banned in 1999.

The plasterers and ‘Artexer’s’ (specialist plasterers) and their labourers would have been in the very high risk category as they were breathing in the dust most of the day.

What about all the buildings that have figured plaster ‘Artex’ ceilings and walls?

Not a problem as long as the surface has been painted over with emulsion paint. Most emulsion paints are basically PVA (the same liquid used as wood glue) and pigments plus water. The water enabled the emulsion to soak into the surface of the plaster and the PVA then dried off sticking the pigment on the surface forming a skin.

The second and consequent coats of emulsion then bonded to the surface building up a thicker skin. That has sealed the plaster in and if there is any asbestos in with the plaster (not all figured plaster contained it though) it is safely contained.

What about scraping it off? – NOT a good idea at all . The best option is to wash the ceiling over to remove any grease and then coat with a dilute wash of PVA (or two). Let it almost dry off and then skim the surface with Thistle Finishing plaster or similar product.

The same applies to walls that have been coated with sculptured plaster. A popular pattern was the heavy relief pattern ‘tree bark’. It will require more than just a skim coat to cover that.

However a good tradesman (yes or trades girl) should be able to skim over without taking the sculptured plaster off. Unless the Artex has been put on very thickly it should be possible for the plasterer to ‘feather’ the edges so the coating doesn’t mean the light switches, power sockets, skirting boards and architrave need moving.

What about the gels that are designed to remove figured plasters?

As I haven’t any firsthand knowledge of how good and effective they are I cannot comment.

However the HSE though state that if large areas are to be removed using the gel or steaming it off then it is ‘notifiable’ and must be treated as a ‘hazardous material’ . That then becomes a specialist job using full precautions and specialist equipment. The disposal of the waste also becomes a hazardous waste . Not putting it in a black dustbin bag and out for the rubbish or down the tip. There is more information on the HSE website.

Who else is at risk? Electricians – they are probably the most at risk when they chase out through the plaster with a ‘wall chaser’. It is a machine that cuts a channel using high speed rotating blades. They throw out so much dust it becomes like a fog. Wearing a dust mask isn’t going to help much if at all.

The manufacturers of ‘wall chasers’ have designed much better machines that have a hood that can be connected to a constant suction machine such as a vacuum cleaner.

However the vacuum holding container must be suitable for masonry dust and the filters capable of preventing dust from the exhaust. Not a domestic vacuum cleaner though.

But my property needs a re-wire and I want additional sockets.

If the walls are finished in ordinary plaster then normal PPE (Personal Protective Equipment) should be worn. Eye protection, ear protection and a suitable dust mask. Polythene dust sheets should be used to cover furnishings and carpets etc.

If the wall has figured plaster treat it as if it is Artex even if it isn’t. There were alternatives being used such as ‘Wondertex’ made by RMC. It was asbestos free (that’s what they told us).

Where Artex or similar figured plasters have been used on a wall that is to be chased out then sheet out with polythene over the floor area and tape the edge to the skirting board. Place a length of wetted kitchen paper along the edge where the wall abuts the floor. The idea is the damp kitchen paper will catch and small particles and heavier dust.

Score through the paint and surface plaster with a sharp knife where the intended chase is to go and use a small hand spray or wet (not dripping wet) cloth to wipe over the chase. Use a sharp bolster chisel to cut through the plaster layers down to the backing coat. Remove the coated plaster into a bucket and take it outside.

The important issues are:

1. The sculptured plaster (Artex or similar) will have been removed in chunks, not dust. There will be some minute dust particles and that is why the wet cloth was required. That will stop the dust.

2. There will be small particles that will fall away (and some larger ones if the original plaster is old and friable). Those will drop down onto the polythene sheet and be caught up on the wetted kitchen towel.

3. Cleaning up is easy – kitchen towel can go in the refuse. With the small amount of potential dust it is not a listed hazardous material like asbestos. A quick wipe over the polythene with a damp piece of kitchen towel and dispose of in the bin outside.

4. The rest of the chase depth can be cut either using a sharp bolster chisel, ‘needle’ out and finish with a sharp bolster.

Using your domestic vacuum cleaner is not a good idea . They are not designed for masonry dust and the exhaust will be blowing out into the room.

The size of the dust is measured on microns, so small it cannot be seen with the naked eye and will float in the air if blown about.

A dust pan and brush is better and damp kitchen towel to wipe up the residue dust. Then a quick rinse of the dust pan and brush.

Why isn't it a good idea using my vacuum cleaner?

If there is asbestos in the dust you don’t want it left in your vacuum cleaner. The filtration system isn’t designed to take that kind of dust. Most house dust is relatively soft flakes of dead skin, fabric fibres from clothes, furnishings and small amounts of grit and dust from outside. The HSE recommend a class H vacuum cleaner be used. They are specifically designed for working with asbestos.

A HEPA filter will not stop asbestos particles This is an extract from the HSE information sheet: ‘Never use domestic vacuum cleaners, even those fitted with high efficiency particle arrestor (HEPA) filters as these are not adequate for use with asbestos, and will allow asbestos fibres to pass straight through’.

Some hire shops can help. It isn’t mandatory for just a few holes or a one off short chase but logically it lowers the risk.

Macho, macho Man! – There is nothing macho about not taking precautions for your health (or those around you). The Health and Safety at Work Act requires everyone (no exceptions) to be responsible for their own health and safety and those around them .

I am thinking of having recessed lights put in

A very popular ‘home improvement’. Simple – buy a holesaw from the DIY store, cut the hole, wire up the light – yep simple! Or is it?

Using a ‘holesaw’ attached to an electric drill creates dust. The teeth on the cutter cut through the plaster converting it into dust. The rotation of the cutter and the fan on the drill will blow some of the dust around and into the air. More of the dust will fall onto the person using the cutter; onto their hand, down their arm and over their face.

Holesaws are relatively cheap and easily available so tend to be a popular DIY job. (There are Regulations but that will be another blog)

An electrician should be using a shrouded cutter though. It is designed to keep the dust in a container which fits against the ceiling. The problem is that a figured plaster coating by its design is not smooth and the shroud does not stop all the dust.

An electrician who is working as a business should have a ‘Risk Assessment’ and ‘Method Statement’ if they are working on a large job as a subcontractor. The client and main contractor will require those as part of the Health and Safety requirement.

However the domestic electrician is unlikely to have those. If a ‘one man band’ it’s not a legal requirement however if it is a business with several employees there is a legal requirement. Don’t laugh too loud – I agree I have never come across a domestic electrician who has them, most don’t even know what they are.

In brief:

Whatever the job and whoever is doing it there are risks. The aim is to minimise or completely remove them. Think the job through right up to ‘thanks very much, I’ll be off now – job finished’.

If it is a relatively small amount of work such as drilling a few hole through figured plasters to put say a book shelf up or curtain rail then try and catch as much of the dust as practical onto a damp sheet or two of kitchen paper. The HSE provide a very useful help sheet for drill holes etc.

One practical tip is to use wallpaper paste. It is thick and sticky so dub it where you intend to drill and use either a hand drill or slow speed on a powered drill. The wallpaper paste will catch the dust and can easily be wiped off with damp kitchen towel.

If you intend having a large area such as wall or ceilings steam stripped or gel stripped it becomes a notifiable project . That means by Law you must notify the Local Authority and then carry out the work in accordance with the removal of Hazardous Material . It is really then a specialist contractor job. Not as the various ‘forums’ would have you believe.

If you intend using any of the gel type strippers contact the manufacturers and ask for the Independent test certificate such as BBA (British Board of Agrĕment) or similar, or their Safety Sheets. Some appear to have no independent test certificates or safety sheets. They are a requirement if the products are being used commercially and should be available for the domestic market as well.

If the product is corrosive enough to go through emulsion paint and then soak into the textured plaster enough to de-bond it then it has to be hazardous. There has to be advice as to what to do if it is in contact with skin or splashed in the eye, inhaled or swallowed. There is also a requirement for any contractor to supply that information as part of their Risk Assessment and Method Statement (R.A.M.s).

Looking on the bright side the figured plaster coating may not contain asbestos. If you are worried or just concerned you can have a laboratory test samples and they will confirm whether it contains asbestos or not. It is important to use reputable and registered Asbestos removal firms. Obviously they charge a fee but you will know for certain.

Finally the HSE have stated that the risks are based on moderation. If you intend to put up a curtain rail, book shelf or something similar take the precautions mentioned above. If you intend having a ceiling or walls stripped of figured plaster it would be worth having the material analysed first. If it doesn’t contain asbestos then steaming it off may be okay. The plaster content is calcium carbonate mainly so not a problem.

If the material is Artex that contains asbestos then it is best to employ a registered specialist. Not just a local builder who says he can do it. Reading the blogs on-line is enough to realise there are a lot of ‘so called builders’ that do not know much about Health and Safety.

An excellent website explaining Non-licensed tasks involving Artex:

http://www.hse.gov.uk/pubns/guidance/em4.pdf

Employing a Nightmare!

183:755862559 (Robert Cooke) — Tue, 08 Jan 2019 21:06:00 GMT

What's the best way of getting a decent job done?

Getting someone in to install central heating, a new bathroom suite, or electrical works should be straightforward. Get 3 quotes (not estimates), look for trade association logo, and then reviews. Simple.

Reviews – who do you believe though? The reviews on the trader’s website? They could have written them themselves. What about the various websites that advertise you can 'trust certain traders'? Surely they must be true? In theory yes – in practice NO!

Ah but they must be okay as they have a trade logo stating they are a member of XYZ trade. Nope – That doesn’t mean much other than they pay an annual subscription. Technically a business can be expelled if there is a good reason for it. You can check if a trader is a member if you know their membership number. Rogue traders have been known to put various trade association logos on their vans and letter heads even though they are not members.

What about the guy who advertises that he has passed his GNVQ? It’s an achievement but not really a trade qualification.

A recent case:

A lady wanted full central heating put in to her terraced house. The neighbour had his done a few years ago by British Gas and they did a great job. Problem for the lady was she couldn’t afford the British Gas price.

Never mind, a freebee newspaper came through the letterbox with a flyer. It was advertising a Central Heating business. Local and had 5 star rating with one of those firms who claim you can trust their members (You know the one).

The reviews were really good and keen prices. She had someone round who explained what they would do and then send an estimate through the post. So far so good; A local business, has the Gas Safe logo on the letter headed paper. They wanted 50% up front and the balance when the job was completed. (Not so good)

The lady accepted the estimate and the contractor arrived in a beaten up old van. Two guys, neither of which were the guy who had been before. Lady went to work leaving the contractors to get on with the job.

I was working next door and could hear the noise through the wall. It sounded like they were using a Mickey mouse drill, not pneumatic masonry and took forever to drill each hole. Their tools were certainly not tradesman quality. DIY at best.

Two days after they started the neighbour asked me to look at what they had done so far. They had the gas boiler fired up and the radiators were hot, but what a mess! The surveyor (Boss of the firm) had agreed that gas pipe that was to have been run up behind the stairs (as it had been next door). The contractor had run a new pipe that went down under the floor.

The 22mm dia pipe had been notched into every floor joist across the house. 100mm joist with a 35mm notch out of it right next to the bearing (support). The pipe diameter then increases to 25mm dia before going up through the floor into the room above. It then reduces back down to 22mm dia before going into the loft. From there it drops down to feed the boiler in an upstairs back bedroom.

Next door also had their boiler fitted in a cupboard in the back bedroom. Their gas pipe was 22mm diameter only and was neatly run from the cupboard under the stairs, through the first floor up to the boiler. Not noticeable other than in the stair cupboard.

In contrast the lady now had very deep notches in every floor joist next to the bearing. (Apart from the notches being too deep they should not be anywhere near the joist bearings as stated in the Building Regulations and TRADA documents).

There are unsightly pipes in the corner of the main living room and the main bedroom above. The water pipes to the radiators have been run above the floor even though the original surveyor had assured her that the pipes would be run under the floor.

As you can see by the photos the fitters were not good tradesmen. Cowboys at best.

So what happened next?

The lady could smell gas so she called the emergency line. They arrived and found that one of the many compression fittings had not been tightened enough. (The fitters should have tested for gas leaks before they had left for the day).

The Gas Safe were called in to inspect the work.

The contractor is known to them but is still in business. He has signed the work off after putting all the long list of things that were not in compliance with the Gas Regulations.

(The photo's were taken after he had put the work right. According to the contractor the work was okay now)

The end result is the lady still has the notches in the floor joists, still has varying diameter gas pipes with an end pressure on the very minimum feed for the gas boiler. The pipe work still runs up the walls and over the floors.

It has been an impossible task to find another contractor to put the work right. Many refused even to look at the job and those who did say that it is not something they want to become involved in.

Take the contractor to Court!

Not worth it. The contractor is listed at Companies House so it was easy to check. He has declared assets of less than £500. Even if the lady had the money to take the contractor to Court it is unlikely that he would pay her for the damages and the money he took as a deposit.

Back to the start then

How to select a contractor

Recommendation - Good tradesman often don’t advertise as they get more than enough work from word of mouth.
Homework - Use the Internet to see if people are complaining about the business. There‘s normally three sides to each story; the customer's side, the tradesman's side and the truth.
Companies House - Check to see the trading accounts. Also if there have been lots of changes of directors. (The firm in question used to have several directors but they had all resigned several months ago. That included family members).
Bad signs - If a contractor wants 50% of the bill up front it could indicate a cash flow problem. (If local suppliers won’t give credit to a business it indicates they know something is wrong).
Statements - If the surveyor states certain things will be done ask for it to be confirmed on the quote. Words are cheap and if it does end up in Court having it in writing is an advantage.
Estimates V Quotes - Ask for a quote. The difference between an estimate and a quote can cost you dearly.

The difference between an estimate and a quote:
An estimate is approximate. They think it will cost xyz. They can invoice you whatever they like afterwards as you have accepted the estimate.
A quote is specific. They will do the job for £x. If they do more work than they quoted for then they require more money. That is reasonable.

For example a plumber quotes for replacing an old boiler. When he takes the old one off he finds the wall behind is not strong enough to take the weight of the new one and additional steel brackets are required. That would be a reasonable extra. In contrast the contractor hasn’t allowed for enough pipe work, fittings and a special flue. Sorry he should have known that – his mistake and should not charge more. However things do happen and a reasonable customer would probably accept the mistake and agree to pay even though they are technically not obliged to. Any decent tradesman would be too embarrassed to admit he had messed up and would put it down to experience.

Contracts are technical documents. Many, if not most small trade contractors do their own quotes and or estimates. Many, if not most have not been trained in the documentation side. They can be an excellent plumber or electrician and get plenty of work but when it comes down to paperwork it is not their forte. According to statistics more people go out of business due to the paperwork side than because they are bad workers.

There's more tips on getting jobs done in Buying Your First Home Handbook

The truth about thermal insulation

183:755862559 (Robert Cooke) — Wed, 02 Jan 2019 11:41:05 GMT

Why thermally insulate anyway?

Hot always goes to cold unless energy is used. It cannot be stopped, only slowed down. So those companies who claim they can stop heat loss are kidding you.

Heat is normally the product of molecule collisions. Similar to your hands becoming warmer if you quickly clap them together for a short period.

In solid items the molecules cannot move much other than vibrate therefore requires a lot of energy to keep the vibrations going. That is why it takes a lot of energy to heat dense materials such as metal, masonry and glass. (Technically glass is a super cooled liquid as opposed to a solid).

Materials that are made up of thin membranes with voids between them have a mixture of solids and gases. Timber is a good example. Softwood has millions of very small tubes termed trachieds. The walls of the trachieds are very thin cellulose. The air trapped inside the tracheid has very few molecules. The ratio of cellulose wall to void is important.

Due to the cellulose walls being very thin the amount of thermal energy required is small. There are not many molecules to move and the vibrations take longer to slow down.

The thermal insulation qualities of timber are very good, especially softwoods. In comparison PVCu the density of European Redwood is about twice that of extruded PVCu. The former being about 510kg/m3 compared with about 240kg/m3.

However it isn’t an easy comparison. The heat transfer through the material is dependent on how much connection there is between the components.

A dense material can transfer heat easily by conduction but if there isn’t much of it and it isn’t continuous then it can be a good insulation. That is why fibre glass loft insulation is a good insulator. The main component is glass which conducts heat easily.

If the glass is formed into fine fibres it would easily fall apart therefore the manufacturers extrude thousands of fibres from one angle and then thousands at right angles forming a mat like layer each time. The layers build up to form the thickness of the insulation.

Air is trapped between the fibres. It cannot move therefore the few molecules in the air will not transfer heat energy very easily, hence making it a very good insulating material. The insulation is sold in compressed rolls making it easier to transport and get through a loft hatch. The rolls must be ‘fluffed’ up just like a duvet on a bed.

The manufacturing process described has the benefit of added strength preventing the roll of insulation falling apart. ‘Earthwool’ is the brand name used by Knauf. The base material is made from recycled glass bottles therefore making use of waste that would otherwise have gone to landfill.

The thermal value is very slightly less than that advertised for similar insulation however the difference is negligible. However the cost difference is noticeable.

The fibres are long therefore create less dust when the material is handled. It is still advisable to wear a dust mask.

The heated air in the room has risen to the ceiling. As it is in contact with the plasterboard the air temperature will raise the plasterboard temperature until they are equal. The process will cool the air as the energy is transferred. The other side of the plasterboard will naturally be cooler therefore a heat flow will continue until the full thickness of the plasterboard is the same temperature as the air in the room. In reality the flow will actually be cooling the air as all of the molecules in the plasterboard use the energy.

Some of the heat will then pass to the glass fibres and they will heat up. So the glass fibres touching the ceiling will be heating up until they are the same temperature as the ceiling plasterboard. The trapped pockets of air will very slowly increase in temperature.

The temperature within the insulation will cool down gradually as less heat energy is available until the top of the insulation will be at the same temperature as the air in the loft (cold).

There is a point within the thickness of the insulation where it has lost much of the heat energy. Beyond that point putting more insulation to make it even thicker is a waste as there is not much heat energy to save. That point has been calculated at about 270mm thick.

Installing loft insulation

There are several good videos on YouTube showing how to insulate a loft. However some of the technical details are missing. For example in a typical loft the ceiling joists will be 100mm deep (4”). The space between each joist can vary depending upon the span of the roof or room below and the size of the other roof members.

Insulation as previously mentioned is supplied in compressed rolls held in a polythene sleeve.

Measure the width between the joists and using a tape measure and a marker pen put a line on the sleeve. Then repeat several times around the sleeve so that when cutting the section will be parallel. You may find the roll has been pre-marked making it easier to cut. If an old carving or bread knife is available it makes cutting the roll much easier. (If you use your normal carving knife it will require sharpening afterwards).
Place the cut section still in its polythene sleeve roughly in the position you will be starting at. Then cut the sleeve and unroll the insulation fluffing it up when unrolled.

That's straightforward but what about all those cables and junction boxes?

Depending upon the age of the property, and more to the point when the cabling was run will make a difference. Also the quality of workmanship and materials used.

Lighting cable should be a minimum of 1mm² cross section of each wire. The old cables were typically insulated in rubber; red for live and black for neutral. There was not an earth wire within the cable. Some electricians ran a bare earth wire to specific fittings. There were different versions of outer insulation from cotton covered rubber and occasionally lead.

More recently the cabling would have PVC insulation around two cables; live red and black neutral. Between them a single wire without any insulation for the earth line. This too is very old and probably out of its useful lifespan.

If either of those types of cable are present contact a qualified and experienced electrician for advice. DO NOT leave it and insulate over it as it is dangerous. Also do not try moving the cables as the old rubber insulation is well past its useful life and will crack to expose the wiring.

Modern cabling has light grey or white outer insulation with blue and a brown insulated inner wires. The earth line is still bare wire running in between the blue and the brown wires.

Enter 'The Problem!' - DIY man (or woman)

Since the 1950’s DIY has become popular. Why pay someone for something you can do yourself?

The easy answer is would you do your own dentistry on you and your family? Why not?

There are several things to consider if it is to be done safely. Cabling should run along the ceiling joists and be clipped ideally near to the top edge. Light fittings were normally pendant type secured to a length of floor board fixed at both ends to the ceiling joists. The lighting cable would run over the board and through a hole and attached to the ceiling rose. Simple, neat and safe.

DIYer or cheapo electrician. Run the cable loose anywhere and everywhere as can be seen in the photo's above. Apart from a trip hazard or becoming caught up with anything put in the loft space it is all to typical.

There are other reasons / excuses:

the 'electrician' doesn't want to be in the loft for very long (in the summer months it can be very hot in the loft - or very cold in the winter).
The loft is full of stored items so it is difficult to work unless the loft is cleared first.
Running the cables the shortest route = cheaper on materials

Does it matter?

When the insulation is between the ceiling joists the cables will then be on top of the first 100mm (4"). Then placing another 170mm (7") or 200mm (8") on top of the cables sandwiching them in is going to prevent the cables naturally cooling.

Another very common issue is recessed spotlights. Very popular halogen or LED spotlights are cut into the ceiling. Halogen light bulbs produce a lot of heat. If in a ceiling of an upper floor the heat can normally dissipate within the void. However where they are installed in the ceiling of the roof void there is a problem with insulation.

If the insulation covers the lamp holder and transformer there will be a heat build up. The heat can be enough to melt the transformer casing leaving the bare wires exposed with a potential of electrocution if touched. Fire is also possible. Glass fibre will not readily burn as glass is non-combustible but it will melt and char. Recessed light fittings should have a protective heat cup over them that enables the insulation to continue over the fitting but leaves enough space to allow the dissipation of heat produced by the light.

LED lights do not produce much heat but should be protected from the insulation with a cup over the fitting.

Bathroom / shower room extractor ducting

There are several different types of ducting but they all have the same function. To enable humid air to be blown out of the building. Insulating the loft will reduce the heat that would be lost via the ceiling therefore any ducting will be even colder after the ceiling has been insulated. There are insulated ducting tubes available relying on the heat from the ventilated room keeping the duct warm enough to prevent condensation.

Ordinary convoluted PVC ducting will very quickly condense the water vapour and form condensation. If the duct leaks damp patches will form on the ceiling. Ideally if possible have the ducting without any insulation below it. The heat from the room will go through the plasterboard and keep the ducting warm. Place the full amount of insulation over the top of the ducting so that it in effect is protected from the cold. Ducting should have a natural fall towards the outlet for the building so that any condensation will trickle out of the building.

Any water storage tanks in the loft should have a close fitting lid and insulated on all sides and over the lid. If the water tank is supported over the ceiling joists there should not be any insulation below. It used to be said that not having insulation below the tank stopped the water from freezing. In reality the insulation around and on top of the tank should do that. Cold water storage that is on a high level platform is more susceptible to freezing therefore it should be very well insulated. There are kits available that include bags of insulation material and straps so it can be removed for maintenance. Ideally look for water tank insulation that meets 'Water Bye-Laws'.

Water pipes should have pipe insulation around them. There are different types and materials including foamed plastics, hemp bandage, and bubble wrap with a foil layer.

The foamed plastic insulation tubes are very easy to use if the pipe clips are long enough. The insulation tubes are available in 15mm and 22mm diameter meaning that is the size pipe they fit. There are other sizes available but normally used on commercial systems. There are are also different grades that claim better insulation qualities. Are they worth paying a premium price for?

The water pipes in the loft are likely to be from the water storage tanks down to the hot water cylinder (cold feed), cold feed to the shower and bath, could be to the basin depending how the plumber ran the pipes. Those pipes will be full of water all of the time so need to be well insulated. There will be a pipe that takes the water to the tanks. It is part of the mains pipe so it will be under mains pressure and always full of water. It must be well insulated to stop it freezing.

If there is a smaller water tank in the loft it is probably the 'header' tank for the hot water system. There will be a pipe taking the water to it at mains pressure so it must be insulated. There will be another pipe that looks like a shepherds crook. That is a safety pipe from the hot water cylinder. If the boiler controls malfunction and the water temperature goes well over the maximum to boiling point the pressure will push the water up the safety pipe so it falls into the header tank. In normal circumstances the pipe should be empty above the ceiling so nothing to freeze.

Other pipes in the loft may include central heating pipes. Some installers prefer to run the pipes through the loft space to each room rather than taking up the floorboards. Very common where a room has fitted furniture or the modern sheet chipboard floor deck has been used. The pipes in the loft should already be well insulated but it is worth checking.

Pipe insulation is important. In normal winters the roof void / loft is unlikely to become cold enough to freeze water. However in the past the amount of heat entering the loft from the dwelling was enough to keep the temperatures up. Putting the extra layer of insulation will significantly reduce the heat entering the loft so pipes etc. may well freeze. Also there are freak years when the temperatures really fall below freezing and even water mains in the road can burst. So insulating the pipes is a must.

What is more important? The pipe fittings.

A pipe may freeze and burst. Even plastic water pipes can burst. However the fittings such as valves and bends etc. are difficult to insulate. Compression fittings are bulkier than the pipes so foamed pipe insulation will not go round it. That is why some installers use the wrap around hemp bandage and cable ties. The bandage can be wrapped around a valve and then cable tied to keep it in place. The plastic bubble wrap is an alternative but I found that duck tape was the only way to keep in in place.

Service valves such as found on the feed pipe to each water tank should be well insulated but still accessible when needed. The hemp wrap and cable ties works very well.

Why are compression fittings so vulnerable to freezing?

Most commonly made of brass they will conduct heat easily. That means any heat energy in the cold water will be lost through the pipe and even more easily through the fitting. So the area around the fitting will freeze quicker. Moving water freezes at a lower temperature.

Problem

A family goes on a winter holiday for two weeks skiing. They turn the gas off. Why heat the home if they are not going to be there? They arrive back from holiday to find their home completely gutted. Ceilings hanging down, carpets, sofa and everywhere soaked. They go upstairs to find exactly the same thing, everywhere soaked.

The neighbour pops round to say they had heard noises and knew they were away. Probably the ceilings falling down. The emergency services turned off the water at the road stopcock. The bill the insurance company paid out was in excess of £47k. The family had to live at a local hotel whilst the house was dried out and completely refitted. What was the cause? An un-insulated cold water pipe valve in the loft.

The water had been still for a long period and the weather had been unusually cold. The water in the pipe had frozen and expanded enough to push the copper pipe out from the olive. (A small ring of metal that forms the water seal in a compression fitting). The mains water pressure was enough to then to push the ice plug out and continue to gush into the property.

Yes it is important to insulate all the valves and elbows properly.

Condensation & mould

183:755862559 (Robert Cooke) — Wed, 12 Dec 2018 14:13:21 GMT

Heating Issues

We’re following on with Tracy and Roger and their apartment being expensive to heat.

As their apartment has very high humidity levels the cost of heating will be higher than it need be.

To heat anything be it a brick, a saucepan, a kettle full of water, they all require energy. However the amount differs with each material or liquid. Water for instance requires a lot of energy to heat it but it also holds heat reasonably well.

If the weather is very hot and humid our body sweats to try and keep us cooler. The idea is the sweat being water will absorb heat energy and cool the surface of the skin. Conversely if we are feeling cold our body stops producing water vapour and raises the fine hairs that cover the body in order to trap air from moving. Still air is a good insulator.

The bottom line is water and wet things take a lot of energy to try and raise the temperature. Dry air takes far less energy to heat it. Tracy and Roger have, or rather had a very humid apartment that made everything damp. Even the air was full of water vapour so it took a lot of energy to raise the air temperature.

Drying the whole apartment out with the dehumidifier mentioned in the previous blog has made the air will be easier to heat. The air is in contact with most things in the apartment so it will raise the temperature of everything it is in contact with until it is all at the same temperature.

Sounds logical and easy enough - what's the problem?

The problem is a bit like a bucket with a hole in it. As you try filling it with water it pours out the hole. The same thing happens to materials. Some materials are dense therefore they have lots of atoms. Heat is the result of the atoms colliding so if there are a lot of them then the amount of energy required to make them all move is a lot.

Dry air hasn’t got many atoms so it will heat up quickly and easily. The gas molecules can freely move about changing the density of the air. The wall in contrast is dense concrete so it has billions of molecules that can vibrate but not move about as such, solid.

So the air warms up easily and tries to make the wall the same temperature. The amount of energy in the air is not enough to heat the wall quickly so in effect the air cools down to the wall temperature. If the wall is damp it will take even more energy to heat it.

However when the wall temperature does increase albeit very slowly it will be easier to keep the air temperature higher. In other words if the heating is on and the walls warm up they will then act as a heat store so the air in the room doesn’t need as much energy to remain warmer.

That is the argument as to whether it is better to leave the heating on low all day or better to turn the heating off when you are not at home.

We could do some calculations to show it is cheaper to turn the heating off when you’re not at home. In contrast we could also do a set of calculations to show it is actually better to have the heating on low whilst you are not at home.

How can it be correct both ways?

Easy; It all depends upon what is in the apartment, what the moisture content is in all of the materials including the relative humidity of the air. Same apartment when it is damp with a high humidity will cost more to heat than a dry apartment with low relative humidity.

Bottom line; Heating air with an electric blow heater is quick especially if the RH is low. However the heat will very quickly cool down as the air comes in contact with all the materials such as the walls, furniture and furnishings. It is and expensive and inefficient way of heating a room or the apartment.

A more efficient form of electric heating is to heat a material directly and let the material heat the air by radiated heat and convection currents. There have been various versions of heater ranging from a cabinet of bricks that required a lot of energy to heat them but made use of cheaper electricity produced during the night and a booster during the day. The electricity went through a different meter known as the Economy 7 meter. The thermal stores were both bulky and very heavy and known as ‘storage heaters’.

The principle was to utilise cheaper electricity at night and give out heat by radiation and convection. The wiring required was heavy duty and too much to run off the normal ring circuits of the property.

As a heating system they are not very efficient and cannot be regulated. If the storage heaters had been set at a specific temperature and the weather changed to a warm period the storage heaters could not be turned down. Conversely a quick very cold period and the storage heaters could not easily respond.

What type of heating have Tracy and Roger got?

Tracy and Roger have another type of electric heater, not a storage one. Their system is basically a metal cabinet with a long wire as an open coil that is attached to a plastic board. It’s a bit like a bread toaster in that the wire (element) becomes red hot and the radiant heat warms the air around it. They are termed ‘convector heaters’.

To make it more efficient a rotary cylindrical fan gently blows the air across the heating element and out into the room. There are three individual elements that can be operated depending on the heat required. The heater cabinet has a thermostat that monitors the air near the heater and regulates the amount of energy being used by turning it on or off.

That type of heating unit is expensive to operate however it will very quickly warm the air in a room. The amount of energy the heater will use means it can be operated safely from a 13amp socket on a typical ring main. (Max 3kW)

Other designs of heater include oil filled radiators. The principle is to directly heat oil in a sealed container. The oil requires a lot of energy to heat it but as a result will slowly cool down therefore providing a steady flow of heat into the room.

The immersion heating elements enable the required amount of heat to be applied to the oil and a thermostat enables a desired air temperature to be maintained.

The problem with the oil filled radiator is the time required to heat the oil. To overcome the issue some models have a timer that can be set so that the heater will operate only during a set time period.

Designs have become more efficient and therefore smaller heaters can produce more heat. The increase in efficiency has been achieved by using ceramic sheets that are directly heated by an electrical element. The material is dense therefore can be made very thin and still give out enough heat.

Back to the plot

Tracy and Roger’s apartment has a dense concrete ceiling which is the floor of the apartment above. Any heat rising will be absorbed by the dense concrete as opposed to building up within the room. Apart from insulating the ceiling there is not much than can be done to improve that issue.

The walls are poorly insulated. Possibly cavity wall construction in some apartments but alas not their one. The walls are literally solid panels of dense concrete that have been plastered over. A layer of insulation could be attached to the wall which would improve the thermal insulation.

As it is, the dense concrete walls literally soak up any heat, they’re heat sinks. When the room heating of is off the temperature of the concrete will drop down to 15°C or slightly lower. That means the air when it is heated again it will need to raise the wall temperature to about 21°C = very costly. If the outside temperature is really cold plus the natural air turbulent of living in a high rise building the wall temperature can significantly fall.

Realistically to reduce the heat loss through the walls is not economical. Various companies state their products will ‘reduce heat loss’, ‘improve thermal insulations’ and so on.

I haven’t named the product or manufacturer however here are some of their claims:

“ product that utilises technology originally developed for aerospace ”. – Hmmm? I wonder what technology they are referring to?

“stops heat escaping through walls and ceilings” – impossible. Nothing can do that.

“minimises condensation, mould and damp, and reduces your energy bills too” – if the wall temperature has not changed and the relative humidity has not changed then the incidence of condensation will not change.

“both the cooling effect of the wall and cold air currents in the room created by the differential temperature zones within a room” – let’s make it sound scientific so it must be true. It certainly cannot change the ‘cooling effect’ of a wall. If the wall has not changed then neither has the thermal characteristics.

What is a ‘differential temperature zone?’ More gobbledygook.

There are several other claims made as to how wonderful their product is at reducing noise.

The product has no independent laboratory test certification or British Standard Kite Mark.

The website reviews mention how ‘the room feels warmer’ . Yes that might be true. ‘Feels warmer’.

Facts based on science

If you have a sheet of expanded polystyrene, perhaps packing materials from something you have bought. Put your hand on it and it ‘feels warm’. What is actually happening is the heat from your hand is being reflected back so your hand doesn’t lose so much heat.

The process it termed conduction. A material or substance that conducts thermal energy (heat) will absorb the energy quickly and our brain determines it is a cold surface, material, liquid.

If the material is a very poor conductor of thermal energy the heat lost from our hand is minimal and the brain determines the item is warm.

Try a simple experiment. Place your hand on a metal table or chair leg and the other on the soft material of the seat or chair back. Which ‘feels warmer’? They are both the same temperature as the air that is in contact with them. Check it with a thermometer.

That is all that is happening; the wall isn’t any warmer - only ‘feels warmer’.

Thermal insulation claim is equally untrue

A thickness of 3.5mm polyester isn’t going to do much at all.

Back in the 1970’s companies claimed their expanded polystyrene ‘wall veneer’ would save £ on heat loss. It was about 2mm thick. They also claimed it made the wall ‘feel’ warmer and people believed them.

Heat energy moves through materials by causing the atoms / molecules to vibrate and collide with each other. As the energy is converted into heat the molecules slow down. There is a theory that when the molecules stop moving there will be no heat. That is the point known as absolute zero and has been given a comparative temperature of -273·15°C.

Unless energy in some form is applied all atoms or molecules they will stop moving.

Tracy and Roger could bond a foam insulation that has a reflective plastic foil behind a bonded layer of plasterboard. The sheet material would be bonded to the concrete walls with adhesive. There are various thicknesses of the thermal lamination that will reduce the speed that the heat will be lost in the wall.

60mm of foam insulation plus the reflective plastic foil layer covered with 12.5mm of plasterboard will make a difference. It is not cost effective but it will make a noticeable and measureable difference to heating the apartment.

Problems include water vapour going through the gaps in the insulation. The foil layer is not continuous. Does it matter? In reality probably not. Technically it ‘could’ enable the water vapour to condense behind the thermal board and lead to debonding or blowing of the adhesive.

The other issues are the electrical switches and sockets would require re-wiring so that the cables are long enough to allow for the thicker wall. The joints around each switch technically could allow vapour to pass through.

The window returns known as the ‘reveals’ will be difficult to insulate especially if the windows have recently been replaced. Window boards will need to be higher and the soffit (the top part over the window) will be much lower due to the insulation. Yes very costly and compared with the saving in energy use it is not economical.

That's the bad news - hopefully they won't be paying out for materials that don’t work – What should we do?

Ensure the electric radiators are the efficient types. There are wall panels that are relatively low Wattage and used for ‘background heating. They are ideal for leaving on all of the while to keep the apartment from getting very cold. That will also help with the condensation situation as the ‘fabric’ (term used to describe all the materials used to form the building) will remain warmer albeit only slightly warmer.

When the apartment is occupied additional heaters would be used. There are mobile ones that have a maximum heat output of 3kW. Dimplex make a Cadiz oil free radiator that will cost about 45p per hour at maximum however the thermostat will turn the heating elements down or off when the room heat is as required.

The other significant energy saver is thick heavyweight curtains ideally with a thermal lining.

A heavy weight curtain that is placed on the window board will significantly reduce the heat going out the windows at night. If there is a radiator on the wall below the window the warm air will be deflected away from the window as opposed to up and behind the curtain.

Having a thermal lining traps a layer of still air behind the curtain further reducing heat loss. Note reduces – nothing can stop it. Putting the curtain up on the window board may not look pretty but the difference in thermal comfort is considerable and at no extra cost.

Window blinds are not as effective as thermal barriers. There are thermal vertical slatted blinds that are good at reducing solar gain and reduce heat loss but they are not as efficient as heavyweight curtain material.

Without going too technical there is air resistance that has an effect. A soft rough surface will slow the air movement. In contrast a hard smooth surface will have little resistance so the air moves more freely.

Nothing in this blog is revolutionary. It is all basic science so why did the architects and designers get it so wrong? The concept of high rise is not a problem. The design and choice of the structure is though.

That is the subject of next week’s blog; heat transfer.

How do I stop Condensation

183:755862559 (Robert Cooke) — Mon, 03 Dec 2018 16:08:28 GMT

6 easy steps to reduce condensation on the bedroom windows.

‘Why do I get condensation streaming down the bedroom windows in the morning? Where does it all come from?

Mostly breathing and as a result of bathing. Moisture from breathing is easy to prove but it might be a surprise just how much water one adult produces.

If the air is cold you can see breath condensing in the air. But we also breathe through our skin. More accurately we expel water vapour through the millions of holes in the skin. The vapour condenses (sweat) and the water then absorbs heat cooling us down.

When we sleep our body temperature needs to cool down by about 1 or 2 degrees. To cool down whilst feeling cosy in bed means expelling water vapour – sweat. It mostly soaks into our PJs and into the bed linen, covers and mattress.

‘How much water are we talking about?’

Weigh yourself before you go to bed. (Ideally in kilograms as it makes the calculations easier). Then weigh yourself when you first wake up. You will be about 0.3kg (300g) lighter. (If you have been to the loo in between times the calculation will be void).

300g of water has left your body in about say 8 hours of sleep. 300g is the same as 300ml or 0.3 litres and that is as water, not water vapour. 1 adult has produced just over ½ pint, (a mug full).

If your home is occupied all day you will have put about 1½ pints of water, (not water vapour) into your home per 24 hours.

Now add bathing. Having a shower will put more vapour into the air as mentioned in the previous blog.

Try this when you next have a shower: Weigh the towel/s you will use before you dry yourself and then after you dried yourself. 1 gram increase will be the same as 1cc of water absorbed into the towel. There are 1000cc in a litre (technically at 20°C).

As a rough guide 100 grams of water is about 0.18 pints.

If you have long hair you’ll probably use another towel around the head. Check the amount of water it absorbs.

Does this sound familiar?

You’ll probably go into the bedroom to dry your hair. Probably leave the bathroom door open. Then use the hair drier to dry your hair.

(You could do another experiment; weigh yourself before showering and then again after showering. The amount of water your hair will retain is actually quite a lot depending how long and how thick etc.).

Now you have damp towels and lots of hot humid air that the hair drier has created whilst drying your hair. Add that to you breathing all night and putting about ½ pint (a third of a litre) of water into the room. Plus the cooler humid air has rolled out of the bathroom across the landing and into the bedroom, down the stairs (if in a house).

All that vapour condenses on cooler surfaces to become water.

You'll probably have the heating on during the day so the water molecules in the air (vapour) become energised and collide with everything. The collisions are kinetic energy and the result is heat.

You have heated the air and that air will heat everything it is in contact with. The molecules in the air will also attract the water molecules that are in the wet towels and in the bed clothes, mattress and so on. That is evaporation and heat helps the process.

The air in the room is now buzzing away merrily. Warm air can hold more water vapour molecules as the air molecules have more energy to move. The solid walls hold the air in so the result is a rise in pressure.

(A previous blog goes through how the molecules pack into space. The more molecules in a given space means the effect of gravity increases. Humid air has more molecules per unit of space. They are packed in = the air is denser = heavier).

The day has ended, Sunlight no more so draw the curtains and keep the heating on. The air is holding a lot of vapour whilst it is warm. A design temperature for a bed room is 18°C. The idea is it help your body go into sleep mode.

Later the heating turns off and the room temperature gradually cools down. Probably at around 3am it becomes as cool as it will get, about 15°C.

The windows are probably much cooler outside than that. Say a cold night at 3am 5°C.

That means any air in contact with the window inside that room will be cooling down much faster than the rest of the room.

If your windows are double glazed the spacer bar (the older ones were aluminium. Modern ones are plastic) will transfer the heat energy even quicker. That is why you see a halo effect where the condensation is all around the edges and more so near the bottom of the window.

If the air is very humid (holding lots of water vapour) then there will be more condensation.

If the outside temperature is very low, less than 5°C then it is likely that the whole of the window glass area will have condensation on it. As more vapour condenses the amount of droplets become too much for the glass to attract. The result is the water streams down the glass.

The water soaks into the wall, soaks and stains the wall paper, soaks into the plaster. The emulsion paint discolours and the dreaded mould spore start to multiply. The back of the curtains, nets if there are any, and the wall below the window all become damp and go mouldy.

Okay, I don’t suffer with insomnia - How can I get rid of the mould and condensation?

1. Keep the extractor fan running for about 30 minutes after you have finished the shower.

2. Keep the bathroom or en-suite door closed or only just open (12mm or ½” max) to keep the humid air in that room. The extractor fan must be working efficiently though. (see below what was found in a pipe behind the ceiling grill).

3. Put the wet towels back into the bathroom as soon as practical and hang them up to dry off. If you don’t have a towel radiator then hanging them over the shower rod or washing line if available. The worst thing is to hang them over the bedroom door or landing handrail if there is one.

4. Leave the bedroom door open after you have finished in that room. Air needs to circulate to mix up the gases. If you have been sleeping in that room possibly with the door shut all night the mixture of gases will have changed. You have used some of the oxygen and produced carbon dioxide, a bit of methane and added to the water vapour.

5. The bathroom door can also be left open after about the half an hour delay. Air circulation is very important part of lowering the humidity levels.

6. If the room has ‘trickle vents’ or you don’t mind having a small window open for a while it will help with the gas balance change over. Ideally a dwelling should have the air changed about once or twice an hour (as if that’s going to happen).

Those 6 points should significantly reduce the amount of condensation running down the bedroom windows.

There are other factors though.

That was one adult in the dwelling. Multiplying by the number of adults and change the life styles.

Here’s another:

Tracy and Roger are a young couple who both go out to work full time.

They live in a two bed apartment in a high rise block. They leave for work at 6:30am and get home about 7:00pm.

A typical day starts about 5:45am, quick shower each, towels draped over the bedroom and bathroom doors to dry. Shower tiles and bath left wet. Shower curtain all wet too. Shut all the windows and lock the doors and off to the station.

The heating is timed to go off at 6:30am and come back on again at 6:30pm ready for when they arrive home. They have an automatic washing machine but no space for a tumble drier.

They have a clothes horse and the washing out the machine is draped over that as it stands in the kitchen to dry off. Mainly shirts etc. and most of the other clothes go to the dry cleaners.

Mould and condensation are a problem. Clothes in the wardrobe and the bed linen are beginning to smell musty. They have recently found a pair of leather boots bought only a few months ago have mould on them. They are now ruined and a throw away job.

The ceiling is the dense concrete floor of the apartment above that has been Artexed over and painted white. Heating in the apartment is by electric heaters in each room. The walls are poorly insulated and the windows have just been replaced with double glazed Upvc windows.

Although they both earn good money they are spending a fortune on replacing clothes and furnishings and trying to heat the apartment.

Can anything be done to reduce the condensation and stop the mould?

Yes is the simple answer. A small machine the size of a small suitcase should sort most of the problems out. Dehumidifiers have been around a while. Some are noisy and don’t actually do a lot.

When I was at the College I had equipment to actually test a machine in a ‘wet lab’. This particular machine is now Mk5 but is really good.

EcoAir DD1 Classic MK5 Desiccant Dehumidifier. It can be bought for under £180.

Why that machine in particular? It has a laundry mode. Leave washing on a clothes horse in the kitchen and almost shut the door. The machine needs to be relatively close to the washing but not touching it. The laundry mode blows warm air onto the washing and sucks air in through a filter near the base of the unit.

The filter helps catch particulates that are pulled in and the air then passes over a silver filter. Silver is known to kill bacteria and that includes mould spores. It isn’t likely to be 100% efficient but any reduction of mould spores is a good thing.

The humid air (being drawn in near the floor level) passes through a desiccant system.

'My friend has a dehumidifier and it’s noisy and doesn’t do a lot. They’re rubbish!'

By the sounds of it they have a compressor type as opposed to a desiccant dehumidifier. There is a lot of difference. Compressor types are noisy. It’s a bit like the compressor on the back of a fridge.

Compressor dehumidifiers work on a basis of cooling rods and the humid air is blown over them to condense the vapour into a tray below. They are only efficient over a narrow air temperature range.

In contrast a desiccant dehumidifier uses crystals that absorb vapour from the humid air and then dries it off as water (hang on that sounds daft – how can it dry it off as water?)

Without going in to it too technically that is what the machine does. The humid air goes over a wheel covered in crystals and they soak up the moisture. The wheel rotates and warm air is blown over the crystals to dry them out ready to repeat the task. The warm air passes over the silver and through an ioniser before being blown out of the oscillating grill at the top of the machine.

The machine is very quiet (there is no compressor). The manufacturer state 34dBA. That means decibel audio. The ‘A’ is the range that humans can hear. Background noise is about 40dBA so it is very quiet.

The laundry mode is when the machine is on full power. Full power is 620W. Compared to a tumble drier that is about 1.7kW at full power the dehumidifier uses about a third of the amount of electricity. Yes you don’t get ‘owt for nowt’,

The dehumidifier will be on for longer than the tumble drier. It will actually dry more clothes than the tumble drier at one time. However on test it used less electricity to dry more clothes than the tumble drier.

The machine will pull up to 2 ltrs of water out of a building and then turn off ready for emptying. If the washing is dry and the relative humidity is just above 30% then it automatically turns off.

It is ideal for Tracy and Roger. It can dry the washing whilst they are at work. If they leave it in the hallway and the bathroom door and all the other internal doors are left open it will dry the whole apartment out. It will take time though.

The first few days will really take the water out. They may need to leave it on all day, empty it when they get home and turn it on again to run through the night. Empty it in the morning and on again for the day. (If it is on laundry mode it uses 0.62kWh or 0.32kWh when used normally).

It'll cost a fortune though?

Not really. A kWh is about 15p. (hours x days x kW x £/kWh x weeks) = (24 x 7 x 0.32 x 0.15 x 1 = £8.06) That would be the cost if the machine is left on 24 hours a day for a week. There would be an offset cost as the other electric heating will not need to be on as much.

Yes it will use some electricity but the benefits far outweigh ruined clothes, smelly clothes, and damp furnishings that allow mould to grow. After the initial drying out of the apartment the dehumidifier only need be used to dry off the washing and an occasional use if the problems return.

Another gadget that Tracy and Roger may want to buy is an RH gauge. For about £10 the small electronic meter will indicate the relative humidity of their home. It is unlikely to be very accurate and in reality it doesn't matter too much. The meter I use on surveys costs several hundred £ so it should be accurate.

The idea is to occasionally check the RH against the temperature. The RH can be high at say 24°C and no problem with condensation. However when the temperature drops at night (3am is typically the coldest time) condensation could be streaming down the windows. A rough target is about 30 to 35%RH at about 20°C. If it is about 70 or 80%RH at 20°C there will be a problem.

Next week’s blog we’ll look at the heating.

Myths

183:755862559 (Robert Cooke) — Fri, 23 Nov 2018 12:42:21 GMT

Moulds and Condensation

The Blog this week is about:

Myths and mis-information regarding Condensation & Moulds

There are Company websites proclaiming they are ‘experts in condensation and mould issues’. They state things like: ‘Get the professionals in’, ‘The condensation experts’. But should you believe them?

How do you know if they are just a website that states ‘pseudo facts’ that are nothing more than just myths? Even Local Councils and Housing Associations get taken in.

Look at some of their facts and compare with actual proven science:

Opening windows

‘Open the window and let all the steam out’ – It helps very slightly however doesn’t do much at all to reduce the condensation around the home. As mentioned in a previous blog dry air is molecules of nitrogen (78%), oxygen (21%) and trace gases (1%) with space in between them.

Humid air is dry air with water molecules (vapour) in the spaces.

Water can be solid as ice, liquid as water or gas as vapour. The molecules are exactly the same with a ratio of 1 hydrogen atom to 2 oxygen atoms (H2O).

Water can vaporise at temperatures well below boiling point (100°C). The evidence is water evaporates from the oceans and seas etc. Leave a glass of water and eventually the water will evaporate. (If you want to find out more it will be in Construction Science Explained – www.buildabooks.co.uk out next year).

The atoms of a water molecule remain the same whether it is water, ice or vapour. As vapour they can float in the spaces between the other gases in the air. That process is termed humidity.

A common ‘myth-statement’ ‘Steam is water vapour’ . Not true. Steam is water. It is water vapour that has condensed in the air therefore it is actually condensation and visible. Gases including water vapour are not visible.

Molecules are more than one atom. It can be the same type or different types termed compounds. Either way although they do not have a weight as such (Atoms have an atomic weight that is a comparison with a carbon atom). Atoms do have a mass though. That mass can be attracted by a greater mass. The greater the mass the stronger the attraction. (Similar to weight).

The planet Earth is made up of an enormous number of atoms. The combined attraction (pulling force) we call ‘gravity’. It’s a bit like a very large magnet will attract a smaller item such as a nail. The nail if magnetised will attract a smaller pin, and so it goes on down the sizes.

Gravity however is a strong attractive force that can go through most things and still attract. It can go through the tallest buildings and still have an effect on an aircraft flying at 35,000 feet in the air. So logically it also has an attractive force on every atom be it in a solid (the aircraft), a liquid (rain comes downwards) and the gases.

If it didn’t have any effect on the gases they would all have gone off into outer space. Irrefutable evidence: the higher the altitude the less molecules. We state that the air is ‘thinner’. What it actually means there are less molecules, less nitrogen, less oxygen etc. and a lot more space.

So what has all this proved?

Air can be dry – no water vapour in it. Very rare though, most air has some water vapour in it even in the hottest deserts.

Atoms have a mass. The more mass in the same volume means there is more atoms for gravity to act on. We term that ‘weight’. If you could take say a gold bar that has a weight on Earth of 6kg then send it to the Moon it would then only weigh about 1kg. The gold bar hasn’t changed, it still has exactly the same number of atoms in it. The only difference is the attraction force ‘gravity’. The Moon is that much smaller so less atoms to to do the attraction.

If air is heated the molecules will become more energised. They will move more quickly and collide with each other. The collisions tend to end up as the molecules bouncing off and going in a different direction to their next collision. All the time that is happening gravity is trying to pull them down to the lowest point and slows them down The result is less collisions = less heat generated = the air cools down.

If a cubic metre of air is considered there will be a given number of air molecules in it at a specific temperature. If the molecules are given more heat (energy) they become more energised and travel faster and further. There will be fewer molecules in the cubic metre as the temperature rises. Fewer molecules means the pull of gravity has less effect. The cooler air will push the warmer less dense air upwards. Warm air rises and that is the reason why.

Evidence: the attractive force of gravity can be compared to magnetic attractive force. The closer together metal particles are the easier the magnet can attract them (ignore friction).

Warm air is less dense than cooler air as there are fewer molecules for gravity to act on. Warm air therefore is displaced by cooler air that has more molecules in the given volume. The end result is warmer air will be pushed upwards by the cooler air trying to get as low as possible.

That was considering dry air only; Nitrogen, oxygen and trace gases argon and carbon dioxide. Now add water vapour.

Water vapour (H2O) has mass so will be attracted by gravity. The more vapour that can fill the gaps in the dry air the denser the molecules. The more effect by gravitational pull and the air is effectively ‘heavier’. At the same temperature the humid air is going to sink. As is sinks it displaces (pushes) the drier air out of the way. If there are walls then the only place the lighter drier air can go is upwards.

It is said it ‘rises’ but it is actually it is being pushed upwards by the more dense air. (Nothing can go upwards without energy being used, not even atoms).

So dry air is less dense than humid air at the same temperature. The warmer the air the fewer number of molecules therefore they get pushed upwards (rise).

The air in the shower will be saturated with water vapour. At its maximum temperature the humid air will be pushed upwards by the cooler air. If an extractor in the ceiling or high up the wall is close to the shower outlet it will pull the humid air out of the room.

The hot water will be flowing over the person and surfaces of the materials around the shower (walls, shower curtains, panels etc.). Those surfaces will be cooler than the hot water but as there is so much water any condensation will blend in with the water.

The surfaces will warm up via heat transfer from the hot water. They will also cool the water down in the process. (example; water at 40°C and surface at 20°C will become about 30°C)

The air around the shower area will be cooler still and condensing the vapour into steam. The visible condensation in the air, steam will further condense on cooler non-porous surfaces to form globules of water. The molecules of the surface material attract the water until there are too many water molecules to support and the globule is pulled downward. Commonly known as ‘streaming’.

The bathroom / en-suite door if closed is keeping much of the humid air in that room. The extractor is pulling the humid air out at a design speed (we will come back to that in a moment). Air, humid or dry cannot be pulled out of a room unless other air is going in to replace it. (otherwise you would end up with a vacuum).

The gap under the door

If the gap under the door is at least 10mm (3/8”) it will let enough air in to the bathroom / en-suite to replace the humid air being pulled out.

For those who are interested: If the door is 762mm wide (2’-6”) then the gap area will be 7.62x10-3m. A pipe 100mm diameter will have a cross sectional area of 7.85x10-3m which is slightly more meaning there will be a greater negative pressure but not enough to worry about.

The gap is normally at the lowest level in the room where the air is at its coolest and most dense. It cannot escape under the door as there is a negative pressure (suction) as the extractor is pulling the air out of the room.

Why do I need to know all that?

Simply having an efficient extractor running before the shower goes on (or running a hot bath) will start the negative pressure so any humid air will be going out of the extractor outlet as opposed to building up in the room.

Opening a window – Hmmm. Based on the science it isn’t going to do much. The main objective is to pull the humid part of the air out of the building and opening a window will not do that.

Having an extractor going with the window open isn’t much good either. It is likely this time of year that the air outside will be much cooler than inside your home so all the extractor will be doing is cooling the room down so it condenses the vapour quicker.

The window is unlikely to be at floor level so all that cooler humid air will still be there. Open the door and it can then roll out into the rest of your home.

Bottom line: Efficient extractor operating before the humidity rises in the room. Door shut and the drier warm air from the rest of your home is used to replace the humid air being extracted. Extractor continues to operate for about 30mins after the shower has stopped. (Door still closed or just very slightly open). That will remove the humid air that is formed by water evaporation. By wiping up as much as possible any water or condensation left on the hard surfaces around the shower it will reduce further humidity.

As an experiment use a container to catch all the water you ring out of the cloth used to dry the surfaces. That would have all had to evaporate into the air. Leaving the extractor on for 30 mins will help to remove the rest of the water you haven’t mopped up.

Extractor efficiency.

The manufacturers provide figures showing how many cubic metres of air an extractor fan is capable of pulling down a tube per second, per minute, or per hour. Some extractor fans have an adjustable amperage meaning the amount of energy used to turn the blades of the fan. More revolutions normally equals more of an air flow.

Air in a room will fill the whole volume and all volumes of containers in it such as drawers, cupboards, wardrobes and that includes the waste tubes in the shower tray, bath, basin and inside the pan and water closet of the WC.

Air naturally contains pollutants including mould spores as mentioned in a previous blog.

Mould requires moisture to enable it to absorb food. No moisture = no absorbed food = no growth. Mould can grow down inside the plug hole tube and into the water trap. A slime builds up and the mould feeds off of that. The tell-tale sign that mould and slime are growing is commonly the smell. Bleach will kill the mould and to a point dislodge the slime from the pipe.

Ideally pour the equivalent of a tea cup full down the plug hole and leave it overnight. Then put the plug in and fill the basin with water (hot or cold it doesn't really matter - however hot tends to work better. When the basin is full pull the plug out and let the water flush the waste pipe through.

It is surprising the amount of slime and hair that will be flushed out. A bath trap can produce about a cup full yet still allow water to go through albeit slowly.

Water is not pure H2O. If it were then you wouldn’t want to drink it as it would taste horrid. Tap water contains minerals that are dissolved in water. Calcium for example naturally occurs in water. It is an essential mineral for our bones and all other creatures that have bones or shells. Chalk is basically Calcium (Calcium Carbonate) formed from the bones of billions of creatures over thousands or millions of years.

Another mineral naturally occurring in water is Magnesium.

Magnesium calcite is derived from chalk (the skeletons of those billions of sea creatures). When rain water (which is slightly acidic) goes into the ground it dissolves minute parts of the chalk. A bit like putting sugar in a hot cup of tea. The sugar dissolves and it all becomes liquid.

Potassium is also a naturally occurring mineral in the ground and dissolves in water.

How do the liquefied minerals help mould to grow?

Compare minerals in water with sugar in a cup of tea. Leave a cup of tea and eventually the water content will evaporate into the air (that‘s if no-one drinks it first). The sugar in the tea cannot evaporate and the molecules join together to form crystals. The crystals are very hard and tend to be brittle. They will bond to most hard surfaces producing a coating of sugar crystals.

Now compare that to the water from the tap. Water that contains a large quantity of minerals in solution (dissolved) is termed ‘hard water’. The minerals are in solution, i.e. in liquid form. The molecules are attracted to other molecules causing bonds.

Calcium is a naturally occurring element, a metal by definition. It can exist in water as solution, i.e. liquid, or as a solid commonly termed limescale. When water passes over other materials some of the molecules of calcium bond to them causing a coating. The higher the temperature of the water or the material the water is touching boosts the bond. The result is the calcium solidifies and coats the material. The most common form is calcite (calcium carbonate). It is a form of limestone giving the term limescale. Basically it is a stone-like coating that slowly attracts more calcium out of solution.

In something like a washing machine or dishwasher where the cold water is heated via a metal heating element the formation of calcite in hard water will occur. (That will be the subject of a future blog – Is it cost effective to stop calcite forming in hard water areas?)

Calcite will also form when the water molecules evaporate. If you live in a hard water area your kettle heating element probably ‘scales up’ – has a crust of calcite coating it. There is also probably calcite around the outlet of the taps and plughole material. If there has been a leaking or dripping tap there will be a deposit of calcite where the water has been.

Calcite will bond to the glazing on the WC chinaware. In the water trap the calcite will bond to the sides, under the rim of the pan and in the water closet box. The surface of the calcite will be rough and porous. What else is in the water? Without putting you off drinking water sufficient to say there are lots of things. Some are in solution and others still as very small solids termed 'as in suspension'.

Some of those ‘solids’ stop off at the calcite and some of those are made up of carbon – and mould thrives on carbon. A different strain of mould but still blackish in colour is able to absorb the carbon and set up home. The occasional flush just brings more food so the mould is quite happy. The flush isn’t enough to wash the mould off.

A few bacteria in with the mould and you now get manufacturers advertising their products ‘Get rid of 99.9% of all known germs’. But there isn’t such a thing as a germ. The word originated in the Victorian period to baffle the uneducated.

Originally the word was derived from ‘germinate’. Plants seeds germinate so the clever Victorians who were dab hand at explaining things like poo etc. told people that bacteria in particular grew (from what I don’t know) so they called the process ‘germs’. Bacteria multiply from a living cell, not a seed so no germination. They replicate forming groups of cells termed a colony.

Moulds grow from spores and not seeds so they can’t be classed as germinating either.

Bleach certainly does kill most things depending how strong the solution is and how long the contact is. There are various types of bleach. Bleach used to strip the colour from hair contains oxygen in the form of hydrogen peroxide.

There is chlorine bleach that contains sodium hypochlorite and sodium hydroxide. That’s the bleach used to clean the loo.

Will bleach dissolve calcite though? No is the easy answer. It will burn the cells of the mould and kill them on contact. It will take the colour out of the calcite if there is any (very light grey if it is thick enough) but there isn’t enough acid to dissolve the calcite.

One of the tests geologist use to distinguish limestone from sandstone is to drip very diluted hydrochloric acid on it. (About 10% dilute). Limestone will fizz violently and gas off as carbon dioxide.

It is not recommended that that strength is poured down the loo though. There are products that contain hydrochloric acid that will dissolve calcite. When hydrogen chloride is mixed with water it forms hydrochloric acid. Other solutions are added that bond with the hard surfaces so that the hydrochloric acid remains in contact with the calcite as opposed to just running off.

If the calcite is removed the china surface will not allow other minerals (plus other organisms that are naturally in water) to stick. No food for the mould to feed off = no mould. The problem is that even using the ‘duck’ shaped bottle it is impossible to squirt the limescale remover into the box section ducting that is behind the loo pan rim so it continues to lurk there.

Don’t be tempted to put it in the water closet box either as it will rot the neoprene gaskets and ‘o’rings and they will leak.

Conclusions:

1. Opening a window doesn't actually reduce much condensation.

2. Moulds multiply by replication and need moisture. They do not have multi-cellular seeds requiring germination.

3. There is no such thing as a germ. It belongs in a pot with hobgoblins, the bogeyman, fairies and so on.

4. Bleach will not remove calcite (limescale). Hydrochloric acid dilute is required. [Vinegar will dissolve calcite but take much longer to do so].

5. Humidity is the amount of water vapour in the air. Condensation is the result of water vapour condensing.

6. Humid air is more dense and will readily fall to the lowest point displacing drier air upwards.

7. To reduce condensation water vapour in the air needs to be removed.

The next blog continues with the myths propagated by so called experts. We will be looking at some of their claims.

Condensation & Mould around the Home

183:755862559 (Robert Cooke) — Thu, 15 Nov 2018 09:39:46 GMT

Condensation & Mould

The Blog this weeks is about: Condensation & Moulds

Now is the time that condensation and mould growth are most noticeable. The temperatures outside are dropping and rain and damp mornings are commonplace.

Here are:

· 6 easy ways to reduce Condensation and moulds around your home

And if you’re interested into the ‘whys and what ifs’ then the science will explain all.

The science behind as to:

· ‘Why does mould grow behind and under my furniture?’

· ‘Why have my best leather boots gone mouldy in a box under my bed?’

· ‘What if I turn the heating up?’

· ‘Why do my clothes get mould on them when they’re in a drawer?’

· ‘Why does the grout on my bathroom tiles go mouldy?’

To start with though:

6 easy ways to reduce Condensation and moulds

1. Install an efficient extractor in the bathroom over the shower area.

2. Turn the extractor on before you turn the shower or bath taps on.

3. Ensure there is a minimum gap of 10mm (3/8”) under the bathroom door. Make sure the gap is above the top of the carpet pile.

4. Have the maximum over-run (30mins) set on the timer. Or leave the extractor on for 30minutes after you have finished the shower.

5. Wipe down the shower walls and shower tray or bath to remove as much water as you can.

6. Keep the bathroom / en-suite door closed or very slightly open to keep the humid air in that room. Stop it spreading throughout your home.

Those 6 easy steps will significantly reduce condensation in your home. Mould needs moisture to multiply and you’ve just reduced that.

The science for those interested:

Air is mainly nitrogen (78%) and oxygen (21%), plus 1% traces of other gases. That’s only a guide though.

Imagine nothing, absolutely nothing. No atoms, no gases, not a single thing – space – nothing.

Now imagine lots of tennis balls and table tennis balls in that space. They can represent the nitrogen and oxygen molecules. There is still space between them though where there is nothing. In that space there will be argon and carbon dioxide. They make up about 1% of the gas content of air.

Now we can put in some other gases into the spaces: Hydrogen and some more oxygen at the ratio of H2O or more commonly known as water. Water can be as a solid (ice), liquid (water) or gas (vapour). It is still H2O though.

Gravity acts on gases in the same way as it does on solids and liquids. The main difference is that the molecules in gases have energy that makes them continually move. They continually collide with other molecules bouncing around in the space.

When there are lots of molecules close together (more dense) the gravity has more effect.

Dry air has fewer molecules than humid air therefore lighter (at a comparable temperature).

Back to the shower – Hot water has put more energy into the molecules. They are moving around very quickly colliding frequently. Eventually unless more energy (heat in this case) is put in the molecules they will slow down and collide less.

The pressure will slowly decrease and more molecules will be in one place (density = mass divided by volume). The humid air will cool down and become even heavier as more molecules gather together.

End result; A hot shower will produce a lot of water vapour (it hasn’t got to be above 100°C though) The water vapour will go in between the nitrogen and the oxygen molecules until it virtually fills all the spaces. That is saturation point. If the air is at a specific temperature it can be calculated how much water vapour it can take up.

As the air cools down the molecules slow down and the collisions reduce. The number of molecules in the same volume increases and the air becomes denser. Cooler saturated air is heavier than warmer drier air. Therefore the humid air will go to as low as it can get – the floor.

Leave the bathroom door open wide and all that humid air will fall out of the room into other rooms, even down the stairs. As it does so the humid air will condense on anything that is cooler than the air. Cold surfaces like walls, windows, ceramic tiles, and carpets.

Furniture such as beds, settees, wardrobes and drawers will all be cooler than the humid air so will condense the moisture. Areas behind furniture are particularly vulnerable as there will be minimal heat (thermal convection). The gap will have a cool wall on one side and cool back of the furniture on the other.

The wall is likely to have plaster on it, or be made from a sheet of plasterboard. Gypsum plaster requires a lot of water to enable it to be fully workable. Literally hundreds of litres are required to plaster out a house. It then takes about a year for it to fully evaporate off if the room air is dry.

The plaster when dry is then full of minute holes that the water once filled. Crystals have formed with tiny gaps between them. The result is a hygroscopic material, meaning it will absorb moisture where available.

Now back to the plot.

Shower of hot water vapour saturating the air. The hot water is providing energy to the air molecules and they are all moving very fast and colliding. Gravity is trying to pull all the molecules downward therefore slowing them down. As they slow down more molecules gather in a specific volume of air and it sinks downwards.

Humid air contains more molecules than dry air therefore it is heavier and will sink.

Any material that is cooler than the humid air will condense the water vapour back into liquid form – water. If it is a non-porous material such as glass, metal or plastic it will form beads of water – condensation. If it is a porous material such as a carpet, bed linen, curtains, clothes then the condensation will soak into the material and it becomes damp.

Hygroscopic materials actually pull the moisture into them (a bit like kitchen towel soaks up spills). The walls and ceilings are plaster and most likely gypsum plaster and will pull in water vapour. Even if the surface has been painted over with a plastic emulsion the vapour can still go though. Water molecules are too big though so they cannot pass through.

So what have we ended up with? Hot and steamy air in the shower room. The air is cooling down and the high humidity air drops to the floor. The door is left open and all that humid air has a greater pressure than the cooler air of the other rooms.

The pressure enables the humid air to roll across the floor and down stairs if there are any (not very common in a bungalow though) filling anywhere it can. As it does so the water vapour condenses out of the air and either forms condensation (water) or makes things damp.

Enter the mould spore.

Air isn’t just nitrogen and oxygen plus a few trace gases. It also contains pollutants. They can be particulates (tiny particles of solid matter that are so small they cannot normally be seen). They are there though. That is what dust is. There is enough energy in air to bounce the gas molecules against the solids causing them to float. As the air cools down, less energy and the solid particulates are pulled downwards by gravity. (Dust settles more so at night when it is cooler and the air more static).

Moulds

Mould spores are microscopic, so tiny they are virtually invisible. They are naturally blowing around in the air. Natural and necessary they are one of nature’s cleaners taking anything they can back into the ground. A dead tree would still be there forever if it wasn’t for moulds and fungi.

The spores float in and out of everywhere including buildings and vehicles. We breathe them in and our bodies have various methods to stop them doing any damage to us. If we have a breathing issue though, or generally unwell the spores can set up reactions. They can cause eyes and ears to itch, throats to become inflamed, breathing difficulties and possibly worse.

Black spore mould is very common. The spores are present in the air as mentioned. If they become attached to a host surface they can soak up moisture and the chemicals it contains. They cannot eat as such but absorb moisture. If the moisture has carbon in it that is food to the spore and it will multiply. More moisture, more carbon = more spores until there is a colony of them.

Sugar is made up of carbon. Cellulose is the natural sugar found in wood and wood based products such as paper and cardboard. It is also a base for wallpaper paste hence; ‘Poly cell ’.

Plaster is hygroscopic and will soak up moisture from the air. The wall is a conductor of heat energy therefore the plaster will be continually cooled down. The plaster will condense water vapour and any wall paper will in turn become damp.

The mould spores can suck up (actually they can’t ‘suck’ they just absorb) the moisture including the carbon content in the cellulose. The wallpaper is a wood pulp product and the paste also full of cellulose.

Mould spores can then multiply very quickly. More steamy showers = more moisture everywhere = mould growth. The cooler areas behind curtains, behind furniture, in and under drawers, under mattresses and in wardrobes are all ideal for mould spores. The moist air will go everywhere.

Now turn the heating up. The air temperature in the room increases. The air is in contact with everything in the room. Some surfaces will heat up to the same temperature as the air. Other surfaces will try to warm up but due to various reasons (All explained in ‘Construction Science Explained’ published next year) they act as heat sinks.

Warm air is less dense than cool air. The air temperatures in a room will stratify with the warmest air at the top down to the coolest at the bottom. (Technically it is the least dense air at the top and the most dense at the bottom. Heat has an effect on density though). Heat sources such as radiators are generally near floor level so the hottest air will be above and around the radiator. That means the hottest air will then rise and push the top layer of warm air aside. That is known as convection currents.

‘Why does mould grow behind and under my furniture?’

Air that is behind furniture, under chairs and beds etc., in drawers and wardrobes will not receive any convection currents therefore remains much cooler. Humid air though rolls everywhere and will condense in those cooler areas.

Mould spores float everywhere. When they find a suitable host they start to multiply very quickly.

‘Why have my best leather boots gone mouldy in a box under my bed?’

That is why mould grows behind furniture, under chairs, settees and bed etc. Store your brand new leather boots you spent a fortune on under the bed. Only wear them on special occasions. Open the box that has been under the bed and ‘Oh Hell! There all covered in green mould and ruined!’

Floor level is as low as humid air can fall. Floors are normally colder than the rest of the room therefore the cardboard box will condense the vapour and absorb moisture. The humid air will enter the box as well. Leather and the linings are natural materials and contain carbon. They also contain fats. Black spore mould has a cousin that is blue/green.

It actually prefers fats and thrives on leather. So the moulds share the spoils with the black mould enjoying the cardboard and parts of certain lining materials. The cousin has a feast on the leather and really gets down into it. If there is any natural threads used for stitching then both moulds can absorb together.

‘Why do my clothes get mould on them when they’re in a drawer?’

The same is true for clothes in bottom drawers and in wardrobes. The clothes are kept away from the warm air so readily condense the vapour from the humid air and become damp.

Cotton contains carbon and the threads used to sew man-made fibres of plastic fabrics are commonly cotton. That is why clothes can allow moulds to grow on them. Bed linen; ‘poly cotton’, ‘flannelette’, Egyptian cotton are all food stores for mould.

‘Why does the grout on my bathroom tiles go mouldy?’

‘Why do I get mould on my grouting. That isn’t made of carbon is it?’

Most domestic use grouts are cement based. Cement is made from calcium carbonate (chalk) and that is the source of carbon. The grouting is micro porous and to a very small extent will absorb some of the moisture. Washing your hair with a conditioner, or using a body wash will add to the food that moulds can survive on. Conditioners in particular contain proteins.

Why do we shower? To wash body fats, sweat and bacterium off us and hopefully down the plug hole. However some remain on the wet tiles, shower curtains, shower tray or bath.

1. That was number 5. ‘ Wipe down the shower walls and shower tray or bath to remove as much water as you can’.

By wiping up as much of the condensation and aerosols as practical and squeezing them out down the plug hole the better.

The next Blog continues with Condensation and Moulds around the house.

Building Surveys

183:755862559 (Robert Cooke) — Sat, 03 Nov 2018 12:52:28 GMT

How can having a Building Surveyor look over the property save you money?

Buying property can be very stressful. You find something you like and hopefully can afford. It's not a new build so it won't come with any guarantees or warranties. 'Caveat emptor' - let the buyer beware!

You'll be paying stamp duty, legal conveyance fees, valuation fee and so on so why pay out for a Building Surveyor?

The house I surveyed this week was built in the 1950's, roughly 70 years ago. It had been through long drought years, wet years, cold year etc. so things will wear out. When you look around the property the main focus tends to be on what you can do with it. Settee can go there, tele' can go on the wall over there, kitchen needs a bit of an update, bathroom's not bad and the main bedroom is a reasonable size. And so it goes on.

A Building Surveyor isn't interested in any of that at all. He or she will be looking at the roof lines, chimney condition, whether all the opening windows actually open easily, doors shut properly, locks actually lock, drains are working and so on. Basically all the nuts and bolts that keep the building together. The surveyor checks for anything that moves that shouldn't, has a crack in it, a chip out of it, water in it when it should be dry.

Looks in spaces behind furniture, looks for strange marks, different materials, checks lights work, sockets have been wired up correctly, looks for signs of condensation, mould, mildew and a whole gambit of issues that you wouldn't dream of looking at when you view the property. The house I looked at was very neat and tidy and very clean, not a quick wash round. That made checking for condensation and moulds very easy as there were no tell-tale stains anywhere.

The vendor was a keen DIYer. Very good at decorating and gardening. Not so good at complying with Regulations though. A Building Surveyor should be familiar with various styles of building and materials that would be used. If a room proportion looks out of character or sounds strange when tapped interest should be shown. Has the position of a wall been moved? If so should it should have had Building Regulation approval or a Building Notice Certificate?

Many people just knock walls down to make two rooms into one. A bit of steel and plasterboard - all done. Is it safe though? Was the wall a buttress wall, part of a cruciform structure for a semi-detached? It may not have any joists on it but it is required to support another wall.

What about the electrics? The vendor has re-wired the house. He wasn't a qualified electrician but had an electrician put a new consumer unit in. Checking the cabling in the loft it was clear nothing had been clipped, connectors and switches just left loose on and under the loft insulation. A qualified electrician will need to check all of the wiring and sign the work off as complying with the Building Act and Building Regulations.

The UPVC windows had been foam fixed. Not a fixing screw anywhere. Do the windows need fixing screws? Were they fitted in compliance with FENSA and certificated or checked and Certificated by the Local Authority Building Control.

Is it important? Yes is the short answer. It is going to cost money to remedy all the issues. Who is going to pay? The buyer or the vendor? Does it need to be remedied? Again yes. If it is a safety issue that is important. If it is something that needs to comply with Regulations then apart from being an offence if not Certified it may devalue the property especially if something collapses or starts to fall apart later.

If you want to sell in the future then the conveyancing firm will be asking for the information.

There is a lot more information in Buying Your First Home. It is also very useful for anyone considering moving home.

Property Valuation Surveys

183:755862559 (Robert Cooke) — Sun, 28 Oct 2018 16:01:10 GMT

What are Property Valuation Surveys? Facts or misinformation?

Buying property can become a nightmare. It's probably the most expensive thing you'll ever buy is a popular cliché. Probably true so why do so many buy property without having it looked over by a professional?

"The mortgage lender will be having a valuation survey carried out - surely that's good enough?"

'Could be' is the best answer.

The valuation survey is not really a survey as such. Quite often it is a 'drive by' where the surveyor has gone on-line to see how much similar property in the area has sold for and then a quick look from the car (especially if it is difficult to find a parking space). It shouldn't happen, but it still does.

If the outside looks in reasonable condition then a comparison with how much the property is up for (or the 'offer' made) with how much other similar property has sold for - job done and onto the next one.

Example:
George and Betty want to buy a 4 bed detached, 1930's house with a garage in a road where there are similar houses. They put in an offer for £565k.

The valuation surveyor does a quick check for houses sold in that area. He notes a similar detached house with a garage was sold for £575k last year. Another went for £475k two years ago but didn't have a garage.

A quick calculation: £475k +2%pa = £490,190. Put £7 to £10k on for a garage puts it about £491k tops.
(2%pa - the valuation surveyor will know roughly how much house prices have gone up in that area. The RICS also provide guide figures)

George and Betty want a mortgage for £300k against the total price of £565k. (They are selling their property and will have £265k after paying off their previous mortgage).

The valuation surveyor will provide two figures to the mortgage company.

1. The market value - how much it would sell for at today's prices.
2. An auction figure - that is typically about 80% of the market value.

Note it isn't necessarily the price the property appeared at the estate agent though. It is how much it is LIKELY to sell for.

The mortgage lender needs to know how much the property will be worth or likely to fetch at an auction. Why? Well if George and Betty don't pay the mortgage regularly then the mortgage lender can go to Court and ask a Judge to give permission to evict them.

Then the mortgage provider has to sell the property as quickly as possible to try and claim all the outstanding loan. If the property has been significantly damaged such as partly carried out building work, lack of maintenance etc. then the value of the property could be lower than when the mortgage was first arranged.

(The mortgage provider normally takes a gamble that the value of the property will increase each year so it helps offset devaluation due to neglect).

The valuation in this example would suggest the property is worth about £565k. If George and Betty are only borrowing £300k the mortgage provider should easily achieve that amount if it has to go to auction. (£565 x 80%= £452k).

So the valuation survey hasn't gone into much detail other than how much the property is worth. The surveyor should have a look around the property and the property adjacent for a quick check on the overall condition. The roof for example of a 1930's property will probably need recovering with tiles or slates. Slates have a rough lifespan of about 80 years if blue slates and 100 years plus if green slate from the Lake District. If the roof covering looks recent such as concrete interlocking tiles or concrete plain tiles then there shouldn't be any cause for concern.

Conversely old slates, slipped slates, obvious roof repairs etc. suggest it is about time for a re-cover. The valuation surveyor will put that in his or her report back to the mortgage provider. It is usually by way of a retention. That means the survey report will state the roof is in need of re-covering and a 'ball park' figure will be given as to the cost of the work.

The surveyor can use a pricing book such as Spon's or Wessex (now as computer software making it even easier to estimate). The estimated figure is exactly that, an estimate. It is not a quote.

In this example the property at auction should be worth a lot more than the mortgaged amount
(Auction price 452k against £300k to be mortgaged). It is probable that the full mortgage would be approved and comment may be made about the roof covering.

If however the amount to be mortgaged was close to or exceeded the auction price then a retention is more likely. For example George and Betty achieve less selling their existing property and require a £400k mortgage.

Comparing the auction price with the mortgaged amount the result is close. Therefore the mortgage valuation will either be declined and George and Betty will lose their valuation fee. Or it may be approved with a retention.

The figures would be:
Property value at market price £565k
Property value at auction price £452k (£565 x 80%)
Roof re-covering £25k
Auction price less roof re-covering £427k (£452k - £25k)
Mortgaged amount £400k
Difference of £27k (£427k - £400k) is very close.

Property pricing is not an exact science. Although today the value may be £565k next month the value could drop due to other influences therefore the mortgage company try to ensure there is sufficient equity against the mortgage. That basically means if they have to sell at auction the amount of money achieved will cover the outstanding amount on the mortgage. They will also try to recover their costs for Court Action and so on.

Retention
For this example it may be £23k so the retention could be £25k. That means the mortgage provider will lend £375k with a proviso that the roof will be re-covered to an acceptable standard. When the work has been completed and guarantees provided then the mortgage provider will then release the £25k retention and add it to the mortgage.

That means George and Betty will have to borrow or obtain sufficient money to have the roof re-covered before they can add it to the mortgage. The issues will be:
a) mortgages at present have a very low interest rate. The pay back is over a very long period so the repayments are small.
b) Borrowing money will be a lot more expensive especially if your credit rating isn't very good. The repayments will be comparatively more than for a mortgage. If George and Bettys' income just about covers the mortgage and their other outgoings then a short term loan of £25k may not be possible.

How can having a Building Surveyor look over the property save you money? - That's the next blog