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Friday, 24 June 2011

Treating external wood

There are a variety of treatments available for external wood and in this country we tend to look for translucent finishes that show off the grain of the wood and it is these that I shall focus on (although there are actually some excellent opaque finishes available in eco-format as well).

The decision on what to use is largely dependent on a number of factors:

Has the wood already been treated with a product (stain, paint, varnish)?
What type of wood is it?
Will it be in constant contact with the ground / water?
How exposed is it to the sun and weather?
Do you want it to weather or retain its original look?
Is it located close to a pond / water, or will it be used in housing pets / bees?

If wood has already been treated it is important to know what it was treated with (so remember to make notes on this type of thing when applying as most people will forget over time). If the wood has an oil based coating it might be that you have to re-use this product (unless the product is really well weathered and the preservative has been really leached out of the wood). So for existing coverings your choice is now really limited if you want to go down the eco-route.

Some woods require certain treatments, so a hard wood generally requires a thinner preservative than a soft wood as the grain is tighter. Also some woods have natural tannins or oils that might react with certain products. So if in doubt use a wood oil that matches the  timber. Larch oil for larch for example.

For timber that is to be in constant contact with the ground it is important to treat the wood prior to it being placed in situ. I would also recommend leaving any preservative to soak into the end grain overnight to really give this most exposed of areas a chance to soak up protection as much as possible.

For wood that is really exposed to the elements there is a need to use treatments that will help it to stop expanding, contracting, splitting and degrading. You may wish to protect the structure with a 'disposable shield' like some old pallets or plywood in really exposed conditions. Using really high quality treatments in highly exposed areas is important as it will save you a lot of time in the long run from having to re-treat every year. This is also true for locations where access is an issue.

If you want your wood to retain its original colour then using a UV stable treatment is important. Clear treatments are not generally UV stable as they have no pigment to protect from the UV light. However there are some companies who make clear treatments with a UV protector in. Notably Osmo.

Many treatments are not friendly to wildlife. They are designed to protect against things like mildew, rot and insect attack, so if you want a treatment that does not contain biocides etc then you need to be careful in what you ask for. Natural products are not necessarily safe for wildlife as nature has its own toxins. So using treatments that are safe for your pets / bees / ponds etc is possible, but you will sacrifice a certain level of wood protection unless you treat the wood prior to installation and seal up water based biocides with an oil top coat.

So what do we recommend?

Generally we look to Osmo for their wood treatments they have a huge range of products for all situations. Auro though do a very good water based wood stain range and the earthBorn Varnish is very safe to use although not as durable as the Osmo. For more info contact Osmo or the Eco Home Centre for advice.

Insulating solid walls

Old houses are seen as being a real problem with regards to carbon emissions. Their walls are seen as being really inefficient and difficult to treat. When we use computer programmes to calculate how efficient our homes are we use something called rdSAP (this is Reduced Data Standard Assessment Procedure). With this a U value figure of 2.1 is used. U values are a measure of how thermally efficient a building element is. The lower the U value the better the insulation of the element. New housing is commonly built with a designed U value of 0.3 in the walls. So 2.1 looks really bad. However, research has recently shown that most solid walls actually have a U value of between 0.7 and 1.6, so a lot better than we give them credit for.

Nevertheless, with the need for carbon reduction, we do need to improve the efficiency of this type of housing stock (the old terraces, country cottages, barns etc.) So how best to do this?

Before we can start to look at options we need to understand how walls work and this involves looking at how they were made and what they were made of. For more info on this look at the blog below South Wales' VictorianTerraces - Home, House or Castle?

So given that we need to preserve breathability what can we use?

There are a number of options here, assuming that your house still has its breathability in tact. If you have cement render on the outside that is trapping in moisture, just by removing this and allowing the walls to dry out you will see a 30% improvement in the thermal performance of your walls (approx.)

The main options you have are based on where you can insulate. Insulation can be placed on the outside or the inside. Ideally you will look at external solutions. This keeps the thermal mass on the inside and also reduces any risk of frost damage to the outside (insulating on the inner walls reduces heat flow and can cause frost to come further into the walls).

External insulation options are:

Woodfibre boards (these are wood boards that are mechanically attached to the wall and then rendered over or overclad with timber / brick slips). Remember that you will need to use a breathable render and paint on the finish. For more info visit some of the suppliers websites. Eco Home Centre can access the best (and oddly the cheapest) system if required.

Lime render with added insulating aggregate. This can be vermiculite, perlite, hemp or just a stone dust. All of these are natural insulants and allow moisture to pass through. They can be applied in varying depths, but should be blown onto a wall rather than troweled. A specialist contractor should be employed for this. Eco Home Centre would recommend Welsh Lime Works or Vale Lime.

Internal insulation options are:

Insowall insulating render / plaster. This is a modern, but breathable, product based on lime and nano-technology insulating material that replaces render. So this is great where space is at a premium. It can be put on up to 40mm thick and will improve the insulation value around 70%. I have used this at home and been impressed by it. However read the instructions on the bag, as some conventional plasterers will try and use it like normal plaster. Can take a clay or lime finishing top coat.

Hemp render / plaster. This is a lime plaster with hemp as an aggregate. A good insulator, but needs to be put on quite thickly to get good values.

Sheeps wool or wood fibre insulation blocks. These are similar to the external renders, but designed for internal use. Mechanically attached to the wall and then rendered over.

Studding out the wall with timber and infilling with a natural insulation material like recycled celloluse, sheep's wool, hemp or flax. Remember here to use a wood wool board to provide your internal finish for plastering.

PLEASE, please, remember NOT to use conventional dry walling products like insulating plasterboards, phenolic boards etc. These are not breathable and can cause no end of damage to the walls by trapping in moisture and hiding any damp and mould.

South Wales' Victorian Terraces - Home, House or Castle?

A strange title in a way, but there is rationale behind it. To many of us, the older terrace housing is a home, something to be loved and cared for as it provides us with the shelter, location and amenities that we desire in our towns and cities. To others it is a vehicle for profit, a solid stone face to apply builders lipstick and foundation in order to sell on for a quick buck. Others see the character filled houses as purely a stepping stone up the property ladder, so there is risk that many of these old houses don't get the thought and love that they deserve.

Whichever way you look at these terraces, however, they are all basically mini castles. These are houses that were built using traditional materials and techniques, most notably stone, rubble and lime mortar, just like the castles of old. But like all things there was a slight twist. The industrial nature of south Wales meant that not all the materials were local, some came from as far a field as Ireland and France. Stone was used as ballast in the coal ships on their return journey so no wonder you occasionally find that hit a bit of very hard granite when drilling in your walls to hang a shelf. The famous, and some might say, infamous, black mortar was due to lime mortar being made with ash from the local heavy industries. Bricks were made locally though, you only have to look at the side of Cathays Community Centre to see all the hands prints from long ago that were imprinted in the soft clay. But despite these slight quirks that fact remains that they are historical buildings that require traditional materials and skills to keep them working properly.

If we started covering our historic castles in Wales with modern hard and impervious cement renders, the Welsh public would be up in arms, yet we have, for decades done just this with our famous and distinctive terraces in south Wales. Old stone, brick and ornate lime renders have been lost to pebble-dash, cement renders, stone cladding and a lick of masonry paint. Don't get me wrong I am not against progress and modern materials. Far from it, everything has its place, however these are just wrong to use on the older pre first world war buildings.

Having lived in a 1890's terrace for 12 years I have witnessed first hand the troubles that conventional 'renovation' has had on the building. I have damp half way up my internal walls, random damp patches on the first floor and a cold house. Given that I have a central heating system, two wood stoves and a lovely wife you likes cooking, I should be sweltering. The basic issue is that the walls have been 'damp-proofed'. I use quotes as there is no real way of damp proofing a house with solid walls using conventional pressure injection techniques - the fluid is just pressurised into all the voids in between the stone and rubble. The process also means hacking off the old lime render and replacing it with cement render, this seals up the wall and keeps the moisture locked in. This sounds OK, but the rising damp will always find a way and so capillary action draws the damp up the wall until it hits the 'breathing' lime. It then comes through the render and gives me my trade mark damp patches about a metre up the wall. Meanwhile the wall is sodden and this damages the fabric of the wall and also seriously reduces its insulating values. A wet wall is a cold wall.

The other higher damp is caused by cracks in the render letting rainwater into the structure. Once in it cannot escape back to the outside, so lo and behold it makes its meandering way through the wall to the inside. Water from rain and soil bring salts and these are concentrated in the damp areas and this makes my paint fall off of the walls.

Thankfully, the clay paint that I use for decorating shows up these damp areas and alerted me to them before the mould appeared.

So to solutions, first of all if you haven't rendered your house with cement, please don't. It will cause no end of problems later, either for you, or for the next occupant. The best answer to cure damp walls is to apply a lime putty render (with stone dust aggregate) to the outside. This will draw out the moisture and leave the stone, bricks and rubble dry and hence create a better insulated wall, think of your fuel bills and climate change. Use breathable lime plaster on the inside as well, finished off with some lovely VOC free and extremely matt clay paint (see www.earthbornpaints.co.uk).

If you have inherited a cement rendered house and wish to cure the damp problems, but without hacking off all of the render and starting again, then I would recommend Dry Zone silicon injection cream. This is a DIY solution that creates a damp proof layer in the mortar in between the stone and bricks over a couple of weeks. Any salt infested render and plaster will need to be removed, but this is a much easier job than replacing all of the cement render.

These old terraces therefore have suffered much at the hands of an ill-informed construction industry, but there are ways of making them better and preserving the character of south Wales for generations to come. As pressure mounts for better energy efficient housing and year on year reductions in carbon emissions, surely it is better to refurbish our existing stock to a high level in a way that is sympathetic to its origins, using low impact materials and a bit of care and attention to detail so that the old terraces become beacons of excellence. Our castles once more.

Fed up with filler?

Walls take a bit of a knocking over time. Abrasion, impact, drilling and damp all affect plaster and render. So is there a way of not using conventional fillers?

I have used conventional fillers over time and I have a love / hate relationship that tends to favour the latter. The biggest complaint is that, as an amateur DIY'er I am not so proficient at getting a smooth finish first time around. This in turn leads to me having to sand back the filler I have just put in to get an OK result. Sounds OK-ish, but the conventional fillers go rock hard and are a real pain to sand back. Not only that they are not so good at allowing moisture to pass through and so do not sit particularly well with my old lime plaster.

So an alternative is required. Thankfully there are a range of alternatives.


Auro do a superb internal filler that is based on talc. It gives a brilliantly smooth finish, but most important for me, it is breathable and easy to use and to sand back. It is still very hardy, but the fact that you can quickly sand it back if necessary is a real godsend to anyone like me who needs as much help as they can find when doing running repairs on a house.

Earthborn have a very similar product. Again breathable and easy to use and to sand back. However, the earthborn filler is based on casein and lime, so it can be used as an external filler as well.

Once you have used these products, you will never go back to a conventional filler.

Thursday, 16 June 2011

Water saving and its importance

We think that there is plenty of water in Wales, but with the expansion of mass building projects in the SE of England, how long will it be before there is a National Grid for water? With the climate also set to become warmer and drier in summer in the UK, water restrictions will become much more common place for all of us.
At present every UK home uses a massive 150 litres of water per day, but this could be reduced to 80 litres without causing any real hardship, or compromising personal cleanliness. With compulsory water metering on the horizon this could have a large effect on our pockets.
Potential scarcity of water and cost are not the only issues here either; did you also know that Dwr Cymru is one of the largest electricity users in Wales? In 2005/6 Dwr Cymru used the equivalent of the combined electricity usage of households in Powys, Newport and Bridgend, a population of almost 400,000, in order to bring water to our taps*.
So to help you out here are a few suggestions for low- or no-cost water saving solutions for around the house. All are easy and when combined with other measures like fixing dripping taps and turning taps off when not in use can dramatically reduce water consumption.
Toilets
Did you know that 40% of all household water is flushed down the toilet? There are various ways that this can be reduced without actually replacing the cistern.

  • Your water supplier will send you a free water saving device to put in the bottom of the cistern, or you could equally well use a plastic bottle filled with water. This will take up space in the cistern, causing less water to be used in each flush. You may need to experiment with different bottle sizes to ensure that the flush still operates effectively.
  • You can fit an Interflush® onto the siphon inside the toilet. This device means that you can regulate how much water is used for each flush by holding the handle down for as long as is required. This can save 47% on water use.
  • A retrofit variable flush siphon can be fitted, again from Interflush.
  • A delayed action inlet valve can be fitted. This prevents the cistern from refilling until the flush has finished. This will save approx. 2l% of a full flush.
Showers
Showers use less water than baths, unless you have a power shower (which can use more even for a 5-minute shower). Look at fitting an aerating shower head; these give the feeling of lots of water but halve the volume actually used.
Taps
Aerator heads can be retro-fitted onto existing taps, or if buying new, choose taps with spray or aerator heads.
Dishwashers and Washing Machines
Only buy water and energy efficient appliances (A-rated), and only run with a full load.
See www.waterwise.org.uk for lists of water efficient appliances
Watering the Garden
Install a water butt with rainwater diverter to collect free water. Plants prefer it. Also mulching around plants reduces water loss.
Greywater systems
These take the ‘grey’ water from baths, washing machines etc. and recycle it for use in the toilet. They are easy to install if you are building a new house. For existing buildings there are diverters available to channel grey water into water butts for use around the garden.
For more information visit:
* 2005/6 Dwr Cymru electricity usage was 548 GWh (Dwr Cymru figures)
Average household electricity usage is 3,300 KWh (Energy Saving Trust)
548 GWh / 3,300 KWh = 166,060 households
Bridgend households = 53,342 with a population of 128,645
Powys households = 53,865 with a population of 126,354
Newport households = 56,535 with a population of 137,011
(Census 2001)
Combined figures = 163,742 households with a population of 392,010

Wednesday, 15 June 2011

Which paint for internal wood

Getting the right eco-wood treatment can be difficult. Not many producers make a gloss finish that works as easily as conventional paint manufacturers. This is because natural oils take longer to cure that high solvent content ones, so there is a trade-off between paints with high embodied energy and VOCs and those with natural ingredients and lower natural VOCs. Remember that our bodies and nature are built to cope with natural VOCs (they are present in any oil) and those associated with the pertochemical industry that are alien to us.

Satin / eggshell finishes though are much easier to get with natural paints. These are mostly water based and give an excellent finish, however there are differences between manufacturers. Auro produce a great range of Matt Silk (and Gloss) paints based on orange and linseed oils, whereas Green Paints is based on Soya, whilst EarthBorn have managed to create an eggshell that is totally water based without any oils (ProAqua Eggshell).

So to the most important considerations.

For cost - Green Paints is the most competitively priced. A good quality paint, but it does take some time to cure, so I would not recommend in areas like door jambs, windows or on surfaces that will have heavy items on. I would also only use their semi-gloss. Also only available in a very limited range of colours.

For eco-credentials - Auro is a great manufacturer (carbon zero) that has a good range of paints. They even produce a natural paint suitable for exterior use - their High Gloss 935 paint. This does take a long time to dry to be aware that you will need to leave around 6 weeks to cure. A great range of colours though in their 250 and 260 paints.

For quick drying - EarthBorn ProAqua Eggshell is a must - dry in about 20 minutes and no smell at all. Totally VOC free.

On untreated wood - I would probably use the Osmo Woodwax Creativ range here. One coat for a translucent finish and two for an opaque one, but it does need to go onto untreated wood.

For application on pre-painted wood (not inc. Osmo), give the surface a gentle rub over with sand paper to create a key for the paint to adhere to and then you can either add an appropriate undercoat followed by a top coat, or (most people will just) add a top coat.

For fresh wood either use Osmo, or if using other types of paint make sure you seal any knots with a Shellac, then add an primer, undercoat and a top coat. EarthBorn ProAqua will act as a primer if watered down by 20%.

Wooden floor finishes

Wood is greatly enhanced by a good varnish, the grain is accentuated and the colour deepened. You can also get a really hard wearing finish as well. However what to choose?

Most builders will use a polyurethane finish as this is cheap to buy, however they are not really cheap. Polyurethanes are commonly applied in a number of coats and in between them the surface should be lightly sanded. This give the 'key' for the next layer. So you will need to do at least two sanding tasks. First to get the surface level and prepared and secondly after the first coat (and subsequent coats). So this takes time and hence money.

As well as requiring more sanding there is also the environmental and social costs of using a smelly, high VOC, petro-chemical based chemical on your home's floor.

So an alternative?

Commonly people used a Hard Oil and then waxed this to give a wearing layer. These natural products work by allowing the oil to set rock hard in the wood to make it really resilient and the wax protects this with a disposable layer. This system also requires sanding between coats of hard oil and there is the on-going maintenance of the waxing.

The real alternative...

I believe the best solution is a Hard Wax Oil where the hard oil and wax are pre-combined. This has a load of advantages. Firstly it is simple, it is also very hard wearing and natural but possibly most important, it is economic. No need for sanding in between coats. Just prepare your floor (last sanding grit of between 120 and 150), put on a layer and leave to dry (this is between 4 and 12 hours depending on product), then put on another coat and leave to dry (12 hours). Done!

The catch?

None really apart from you need to put it on really thinly and this goes against the grain of those used to polyurethanes. If you put it on too thick it won't dry.

The best one?

Having spoken to a range of floor fitters they recommend Osmo Polyx Oil. Others on the market can leave tram lines on the wood where you overlap on application.

Which is the best lightbulb to buy?

Lighting is a difficult area to understand - there is a whole industry built around designing lighting layouts, however there are some basics that people should understand when looking into choosing lighting for their homes.

With incandescent lighting slowly being phased out in favour of low energy lights how should be choose the replacements.

Well there are two main alternatives:

Compact Fluorescent  Lights (CFLs) and;
Light emitting Diodes (LEDs)

Both of these offer significant savings over incandescent bulbs, but the choice is made more difficult because of the following factors:
  1. Cost
  2. Energy used (measured in watts) vs light emitted (measured in Lumen or Candela)
  3. Lifespan (measured in hours)
  4. Colour of light (measured in Kelvin - cool white @ approx. 4000k, warm white @ approx. 3,000k and daylight @ approx. 5,500k)
  5. Quality of light (measured in Colour Rendering Index - CRI with 100% being all colours of spectrum)
  6. Quickness of response
  7. Materials used in manufacture (many people have been scared by the mercury involved in making CFLs)
Firstly to CFLs

1. Cost
CFLs are cheaper, but as with most things in life, you get what you pay for. So there is a quality issue. Higher priced bulbs tend to be better made, last longer, have better quality of light and are resilient to being switched off and on constantly.
2. Energy
I tend to work on a factor of 4. So a 15w CFL is equivalent to a 60w incandescent.
3. Lifespan
This varies with cost, but the figures quoted on boxes are when 50% of a batch has failed, so some will last longer than say 8,000 hours, others will not reach this milestone. Megaman bulbs tend to have the longest lifespan of around 15,000 hours.
4. Colour of light
CFLs come in all main colour temperatures.
5. Quality of light
Here CFLs don't fare so well. There CRI tend to be around 70-75% so there are major areas of the colour spectrum that are missing and this leads to us seeing false colours that many people don't like.
6. Quickness of response.
Again CFLs fail a bit here as they take some time to warm up. They work better at higher temperatures and so their brightness increases after about 30 seconds.
7. Materials used.
Most CFLs use liquid mercury to work. This has given the scaremongers a great opportunity to worry people, but it does take some fairly unique situations to be any danger whatsoever from lightbulbs. Megaman have gotten around this issue largely by using mercury in a solid state rather than a liquid one.

LEDs

1. Cost
This is the main issue at present with LEDs they are expensive. You can get really cheap 1w bulbs but they are really worthless if you are looking for light as opposed to dash of colour.
2. Energy
This is a more difficult area, but they are generally more efficient than CFLs with a factor of around 6 to 7. So a 6w LED will give around 36 - 42w of incandescent equivalent, but LEDs are directional and so one pointing up gives less useful light that one pointing down.
3. Lifespan
This varies with cost, but the figures quoted on boxes are when 50% of a batch has failed, so some will last longer than say the average of around 25,000 hours, others will not reach this milestone. Some will claim a lifespan of 50,000 hours, but this might be due to the temperature that they are tested at. The cooler the ambient temperature the longer they will last.
4. Colour of light

LEDs can come in all main colour temperatures.
5. Quality of light
This is where LEDs can excel (although not all). Many LEDs will have a CRI of over 90% so giving a wide spectrum of colour and hence giving a much more accurate quality of light.
6. Quickness of response.
LEDs are instantaneous and so again are ideal for areas where instant light is required.
7. Materials used.
LEDs require more electronics to work and so have more internal circuitry associated with them, but they do not contain mercury or any other poisonous materials.

So recommendations.

Personally I would use LEDs where you want:
Instant light
High quality light
Where changing bulbs is difficult / expensive
OR where you will have lights on for very long periods of time

Apart from that CFLs will suffice and give you adequate lighting.

Applying and using natural eco paints

Once you have chosen your paint there are some tips that you need to know about their use.

Natural paints are largely designed to work like conventional paints, but there are some differences that can make a big impact on how happy you will be with the final product. There are some issues that are specific to certain paints and some generic pieces of advice.


General tips:

Try a match pot first of all. Natural paints are very matt and tend to take on colour rather than reflect it. This means that they will look different in situ than they do on colour charts / computer screens, PDFs, etc.

Use a medium roller or a good quality brush as natural paints tend to be thicker. Many decorators use thick rollers in order to do two coats in one. This is not advisable. There are cases where paints have taken wall paper off of the walls because the weight and enthusiasm of the painters are too great. A good quality brush also ensures that the thicker paint does not show brush marks as much. A natural and synthetic combined bristle is regarded as the best solution here.

Natural paints are more likely to settle, so it is especially important that the tins are mixed well before use. General advice is to stir until you think that it is mixed properly and then do it again!

Most natural paints will cover all plasters, but for lime plasters make sure that it has cured sufficiently first. However clay and lime paints can be applied to lime plasters before they are fully dry.

Cleaning natural paints varies, so be aware that you choose the right type of paint for the wall. So in heavy traffic areas you may wish to get a paint with a higher natural oil content as these are scrubbable compared to most that are wipeable.

Specific tips:

Some paints (clay and lime paints) are hygroscopic (attract water vapour into them) and this means that they are very breathable (a good thing on older buildings) but also that they will pull through stains on the wall and also are more difficult to clean. So ensure that the walls are clear of grease and stains before paint is applied. Alternatively you can seal up the stains with an isolating primer.

With clay and lime paints that are not wipeable you can clean these by using a good quality rubber (eraser).

If you want to use the clay paints (natural, no VOCs, no smells etc.) but want to protect them, you can put a wall glaze over the top. This will create a wipeable surface. However, it will effect the finish (making it more satin) and also colour (slightly darker). If you do choose wall glaze then cover a discrete area (a wall, up to a dada rail etc.) and then you will not notice these slight changes.

When applying clay paint and certain emulsions you will find that they have a slight translucent quality when wet. Do not overpaint. Clay paint especially can look very patchy after application. The best advice here is to walk away and have another look the next day. You should be very pleasantly surprised.

For more advice and products please call the Eco Home Centre on 02920373094.

Disclaimer
Rounded Developments Enterprises Ltd have endeavoured to ensure that the information contained in this report is accurate. However, Rounded Developments Enterprises Ltd. accepts no liability for the use of this information.
Statement of Vested Interest
Rounded Developments Enterprises Ltd are a well-recognised supplier of a range of sustainable building products and as such have a commercial interest in some of the recommendations contained within the report. In some cases, cost estimates have been given on the basis of current quotations for similar equipment supplied by Rounded Developments Enterprises Ltd, and may not be the only equipment available. However, it is our opinion that the study offers an appropriate level of detail in view of the resources available and information provided. The authors have no expectation of any order being placed with them and would welcome questioning of the choice and costs of any equipment.

Saturday, 11 June 2011

Choosing natural eco paint

Choosing paints can be an issue as there are a wide range of considerations that you need to be aware of. Some of which are more important that others.

Natural paints are unlike most conventional paints as they are dependent on their ingredients to define their properties. Conventional paints are designed to do a job on conventional walls, nothing more and nothing less. Many natural paints come from Germany and the people developing them started up different businesses because they had different foci. Some wanted healthy paints, others organic, whilst ease of use was wanted by other people. These aims required different natural materials to obtain the desired outcome.

There are, of course, knock-on effects from choosing the raw materials to provide the various properties. Understanding this is important if the paint is going to be applied in appropriate places and for certain lifestyles and social situations. Thankfully though all the paint manufacturers (being mostly European) have realised that with the premiums associated with natural paints they must produce high quality paints. In the UK we are aren't there yet and the paints are marketed on eco-friendliness but elsewhere it is all about quality, so in buying an eco paint, you will actually get a high quality paint and so virtually everyone who buys one of these paints is a happy customer. The only complaints come from where people have bought the wrong paint for their particular situation.

So here goes:

For healthy non-odour paints (free from VOCs) for asthma / allergy sufferers

Some people are really sensitive to odours. If you suffer from allergies or asthma then choosing paints from earthBorn is a great option. You will get a slight earthy smell, but that is all. Only water is given off when drying.

The earthBorn wall paint range includes clay paint and emulsion.

For organic paints

Many ingredients do not carry an organic standard, however there are oils that can, so organic paint is never 100%, however Auro and Ecos do have organic labelled products.

For breathable walls / structures

Maintaining breathability is key in many older buildings and so choosing breathable paint is vital to allow the walls to do their job. Breathability is not a fixed properties, there are different degrees of breathability.

The most breathable paints are:

Claypaint, chalk paint and limewash / lime paint. EarthBorn manufacture claypaint and Auro do a chalk paint and a paint-like version of limewash.

When using clay or lime plasters you should specify a clay, chalk or lime paint.

For other walls (especially those with conventional plaster) you can use most other natural paints as they all tend to be breathable. However the rule of thumb is the higher the level of oils the less breathable the paint.

For scrubbable surfaces

Where you have high traffic or dirty zones (entrance halls, utility rooms etc.) where you may wish to clean the walls on a regular basis you may wish to purchase a hard-wearing paint. This generally means more natural oils in the mix. Auro do a scrubbable paint Auro 324 and Aglaia have a hard wearing white. These paints have to have fewer pigments and so tend to be only available in lighter pastel colours.

You can cover paint with a clear wall glaze to give a wipeable finish as well. This does change the surface to more of a satin finish and alters the colour slightly and so you will have to use this over a whole wall or up to a dado level etc.

For great coverage

Many natural paints are thick and cover brilliantly. Auro 321 and the earthBorn paints are certainly excellent at covering well. You will be looking at one, maybe two coats.


For matt finishes

Clay paint is probably the matt'est of paints, but the earthborn emulsion and Auro 321 are also good. The Auro 324 has a satin finish due to the higher oil content.

For cost

Cost can be a consideration. So for certain areas like ceilings (where normally a plain white is required) most companies provide a lower priced white option. Auro have their 320 Economy White and earthBorn's paints are cheaper for the white options

For brightness of the white

The brightest white paints are available from Auro.

For cleaning the air

Auro have created a photo-catalytic paint that will stop odours in the home. This paint needs to be in full sun to work effectively and also be maintained in its white colour. A great choice though for certain situations like sunny kitchens, bathrooms and gyms.

For stopping mould

Paint can create a surface that is not mould friendly. By choosing a more alkaline paint it can help to prevent mould from forming. Lime paints are good for this, but Auro also make an Anti-Mould paint. Their system includes boron based sprays that kill mould and then inhibit its growth.


For more advice and products please call the Eco Home Centre on 02920373094.


Disclaimer
Rounded Developments Enterprises Ltd have endeavoured to ensure that the information contained in this report is accurate. However, Rounded Developments Enterprises Ltd. accepts no liability for the use of this information.
Statement of Vested Interest
Rounded Developments Enterprises Ltd are a well-recognised supplier of a range of sustainable building products and as such have a commercial interest in some of the recommendations contained within the report. In some cases, cost estimates have been given on the basis of current quotations for similar equipment supplied by Rounded Developments Enterprises Ltd, and may not be the only equipment available. However, it is our opinion that the study offers an appropriate level of detail in view of the resources available and information provided. The authors have no expectation of any order being placed with them and would welcome questioning of the choice and costs of any equipment.

Friday, 10 June 2011

Repointing solid brick walls

Choosing the right mortar is vital when repairing old walls. Cement is a real problem as most builders will not understand the need to use the right mortar. Even choosing the right lime mortar can be problematic.

Cement mortar is less breathable and hence tries to lock in moisture or makes the moisture pass through the stone or brick. This weakens the stone and brick and hence causes more erosion. Cement should therefore be avoided when repointing older solid walled buildings. Where cement mortar has been used in the original building then using a standard mix is not a major issue.

So on buildings that use softer materials like stone you will need to find the right mortar mix that is weaker than the main structural elements. The main way of doing this is to use lime, however lime comes in a variety of forms: Hydraulic and Putty. Hydraulic also comes in a variety of strengths (generally NHL 2, NHL 3.5 and NHL 5 with 5 being the strongest) whereas putty is the softest. For most re-pointing we would recommend using putty, but you might want to reassurance of a stronger lime and so using 2 or 3.5 is also very common.

In areas where the mortar is likely to be in constant contact with water we would also recommend using a lime putty made from hard limestone rather than one made from chalk.

The aggregate is important as well, so normally we would recommend using stone dust and a pozzalan (brick dust, PFA, GGBS), but most builders will use sand. Sand is not ideal as it is not porous in itself and certainly lime putty does not work well with just a sand mix. Hydraulic lime, though is commonly used with just sand (but we would still recommend stone dust).

The existing mortar needs to be scraped out so that you have room for at least 1cm of new mortar. The wall (and especially the recesses) then needs to be made damp before applying the mortar. The mortar should not protrude beyond the stone / bricks.


For more advice and products please call the Eco Home Centre on 02920373094.


Disclaimer
Rounded Developments Enterprises Ltd have endeavoured to ensure that the information contained in this report is accurate. However, Rounded Developments Enterprises Ltd. accepts no liability for the use of this information.
Statement of Vested Interest
Rounded Developments Enterprises Ltd are a well-recognised supplier of a range of sustainable building products and as such have a commercial interest in some of the recommendations contained within the report. In some cases, cost estimates have been given on the basis of current quotations for similar equipment supplied by Rounded Developments Enterprises Ltd, and may not be the only equipment available. However, it is our opinion that the study offers an appropriate level of detail in view of the resources available and information provided. The authors have no expectation of any order being placed with them and would welcome questioning of the choice and costs of any equipment.

What to do about leaky guttering

Guttering is a vitally important part of a building because it takes water safely away from the fabric of the building. It also makes water available for collection and re-use via water butts or SUDS (sustainable urban drainage systems).
Gutters can leak, this can be due to a number of factors including:
  • Build up of leaf litter / dirt in the guttering
  • Blockage in the downpipes
  • Cracked or damaged guttering
  • Poor seals between guttering lengths
  • Misaligned runs



Plastic guttering is especially prone to these problems because:
1. They expand and contract to a huge degree and this means that the joints are not stable and hence they frequently lose the seal and leak.
2. They are undersized most of the time (as these are the cheapest sizes) and so they get blocked with leaves etc very quickly in areas under / by trees. They also cannot cope with large storms when their capacity is just over loaded. This leads to them overflowing and pouring water down the wall and potentially into the cavity of solid wall structure.
3. They are nasty to fit and so people tend to have the attitude of allowing it to make-do when fitting. This can lead to leaks even before the expansion and contraction hits in.
4. They are quite brittle and easy to break under impact.
5. They are weak and so can break under the weight of snow.

Leaking gutters can be a real hazard for buildings as it allows water to get into the fabric of the building. This can cause damp and structural problems and therefore any leakage / blockage should be dealt with as a priority.

Remedy

Keep your guttering clear from debris by having them cleared every couple of years (or more often if you have overhanging trees).
Use a more stable and longer lasting guttering material. There are options available like steel, aluminium, cast iron and copper. At Eco Home Centre we recommend Lindabguttering because it is relatively inexpensive, easy to fit, well designed, stable, long lasting, easy to fit and can be incorporated into SUDS or other water collection systems.



For more advice and products please call the Eco Home Centre on 02920373094.


Disclaimer
Rounded Developments Enterprises Ltd have endeavoured to ensure that the information contained in this report is accurate. However, Rounded Developments Enterprises Ltd. accepts no liability for the use of this information.
Statement of Vested Interest
Rounded Developments Enterprises Ltd are a well-recognised supplier of a range of sustainable building products and as such have a commercial interest in some of the recommendations contained within the report. In some cases, cost estimates have been given on the basis of current quotations for similar equipment supplied by Rounded Developments Enterprises Ltd, and may not be the only equipment available. However, it is our opinion that the study offers an appropriate level of detail in view of the resources available and information provided. The authors have no expectation of any order being placed with them and would welcome questioning of the choice and costs of any equipment.

Damp on internal walls at approx. 1 m above the ground

It can be very strange to find that you have damp patches in the middle of your walls downstairs. Paint doesn't dry and will eventually fall off, even if it is natural paint. Claypaint applied in these areas will be darker than elsewhere and clearly shows the problem. So what has caused this?

Basically what has happened is that cement render has been applied to the old wall when damp proofing work was done. The old lime plaster was hacked off to a level of approx. 1 m and then new waterproofed cement render and gypsum plaster is applied (see picture below).

Sometimes the builders don't actually damp proof the walls and if they do they commonly use a pressure injection or a cream based silicone. However, this is done when the wall is wet still and this makes it more difficult for the proofing systems to work. Pressure injections are not reliable and the creams, though better, do need to be placed in the lime mortar rather than the bricks.

The installation of a physical damp proof layer is the preferred option for a permanent solution, but this is more costly due to the labour involved.

Many builders, though just hope that the damp will not travel that high and that a quick re-render and plaster will do the job, however, but it does not! The damp from the, normally non-existent, foundations travels up the bricks until it can get out (this is where the new render finishes and the old lime one begins). Hence the damp patch.

The replacement of suspended wooden floors with solid concrete floors can make the situation worse as the associated damp proof membrane under the floor concentrates the rising damp into the walls rather than allowing the damp to be dissipated by the underfloor ventilation.

There is some other bad news as well. The rising water brings with it natural salts and these gradually get deposited in the plaster. When concentrations get too high the paint will react and start to flake off. Once the plaster has been contaminated it has to be replaced.

The remedy?

There are a variety of remedies that are dependent on the work that you are undertaking.

So this can be helped by re-instating a suspended timber floor so that the wall dries out at a lower level.

A physical damp proof course will stop any more water from being drawn up and thus allowing the walls to dry out slowly.
A chemical damp proof course can help if applied correctly. We would recommend using DryZone as it has the highest level of silicone for any treatment that is on the market at present.

You might also hack off all of the cement render and replace with a lime render and plaster. This will allow the damp to be removed from the bricks and dissipated into the internal atmosphere. If this course is taken then you will need to use a breathable paint (preferably a clay or lime paint as these are the most breathable).

Whichever course you take you will need to remove any salt contaminated renders and plasters and replace these. You can seal up the salts in the bricks / stones before re-applying the render, however these finishes are not designed to be breathable.

So there is a set of choices that you can make dependent on your feelings on the use of natural products, breathable structures etc. For more advice please call the Eco Home Centre on 02920373094.


Disclaimer
Rounded Developments Enterprises Ltd have endeavoured to ensure that the information contained in this report is accurate. However, Rounded Developments Enterprises Ltd. accepts no liability for the use of this information.
Statement of Vested Interest
Rounded Developments Enterprises Ltd are a well-recognised supplier of a range of sustainable building products and as such have a commercial interest in some of the recommendations contained within the report. In some cases, cost estimates have been given on the basis of current quotations for similar equipment supplied by Rounded Developments Enterprises Ltd, and may not be the only equipment available. However, it is our opinion that the study offers an appropriate level of detail in view of the resources available and information provided. The authors have no expectation of any order being placed with them and would welcome questioning of the choice and costs of any equipment.

Mould and condensation issues

Ever noticed condensation running down your walls in the bedroom, bathroom and kitchen? Has this in turn created damp problems?
In high humidity rooms condensation can easily occur where there is not enough air circulation or where non-breathable paint has been used to seal up the room. Bathroom and kitchen paint is probably the worst thing that you can use in your bathrooms and kitchens because they seal up the room thus trapping moisture inside and this then can form condensation and damp problems.
Inadequate ventilation is also another major cause of the problem. The smallest (and cheapest) fans are the ones that are usually fitted in bathrooms and kitchens. They are not always the best choice, because they are the absolute minimum required, and this is not always enough. The issue with larger fans is that they use more energy and also increase heat loss. So getting the right size is important.
Where the extractors face is also important. If they are west or south facing they are likely to get blown shut by the wind and hence not be able to extract air properly. So it is worth placing them on the north or east walls to get the best performance and also to stop the incessant slapping of the vent's flaps.
If you are worried about heat loss then this can be partially remedied by using room based heat exchange extractors. However you do need to have a fairly airtight room / house for these to be anywhere near efficient.
A house needs good ventilation and in many homes this comes from trickle vents in the windows and so these should be kept clear.
Many people also dry their clothes on radiators. This just adds large amounts of moisture into the internal atmosphere and so should be avoided.
Condensation is also caused by cold spots in the house. This might be on walls, or on the windows (windows are less thermally efficient than walls). This is way radiators are commonly placed under windows to prevent condensation. So if there are cold spots then condensation is more likely here. This is a structural issue and should be addressed.

Remedy

Ensure that you have adequate ventilation in the house (appropriately sized extractors in high humidity areas) and that they are fitted onto a north or east facing wall. If you have a breathable house (many of the older buildings with solid walls are intrinsically breathable) then by using breathable paints onto the lime plaster then the walls will help to control the relative humidity in the house.
Do not dry clothes on radiators (unless you provide adequate ventilation).
Where you are redecorating existing painted walls, you can use clay or chalk paints to help to ease the problem as they actively absorb and release moisture as humidity levels change.
Insulate where cold spots occur (or cure the underlying structural issue like thermal bridging). Where this is difficult you can use products like insulating paints or thin insulation like aerogels or insulating plasters.
Where these solutions are difficult to do you might want to use anti-mould paints / treatments just to stop the formation of mould.


For more advice and products please call the Eco Home Centre on 02920373094.


Disclaimer
Rounded Developments Enterprises Ltd have endeavoured to ensure that the information contained in this report is accurate. However, Rounded Developments Enterprises Ltd. accepts no liability for the use of this information.
Statement of Vested Interest
Rounded Developments Enterprises Ltd are a well-recognised supplier of a range of sustainable building products and as such have a commercial interest in some of the recommendations contained within the report. In some cases, cost estimates have been given on the basis of current quotations for similar equipment supplied by Rounded Developments Enterprises Ltd, and may not be the only equipment available. However, it is our opinion that the study offers an appropriate level of detail in view of the resources available and information provided. The authors have no expectation of any order being placed with them and would welcome questioning of the choice and costs of any equipment.

Damp around chimney breasts

Damp around Chimney Breasts
Damp is very common around chimneys. This can be due to a number of reasons:
1. Chimney flashings leaking
2. Chimney needs re-pointing
3. Chimney not vented properly
4. Chimney not covered (thus allowing rainwater in)
5. Rising damp

1 and 2 need to be done from the roof and so this requires a professional or a competent DIYer. There are more sustainable alternatives to lead flashing like Z-led and UbiFlex. These are aluminium mesh products. Remember to use the correct mortar for the building. This might well be a lime mortar on older buildings.

3. Chimneys that have not been capped need to be vented top and bottom to dry out any water ingress. Vents therefore need to be in place if the chimney breast has been blocked.

4. There are different chimney pots and some of these are designed to stop rainwater from getting in whilst still maintaining good ventilation. If the chimney is not used then a simple removable chimney cap can be fitted that will stop rainwater, insects and birds from getting into it. This combined with a Chimney Balloon can be an efficient way of reducing heat loss through the chimney in winter.

If the chimney is still in occasional use then it is important to have a chimney pot that stops rainwater ingress. A T shaped pot or an appropriate cowling can either be used as a replacement or just as a bolt-on improvement.

5. The damp can of course be coming from below as well as from above. Appropriate damp proofing methods need to be used here (lime putty render, silicon cream injection into the mortar etc.)

For more advice and products please call the Eco Home Centre on 02920373094.
Disclaimer
Rounded Developments Enterprises Ltd have endeavoured to ensure that the information contained in this report is accurate. However, Rounded Developments Enterprises Ltd. accepts no liability for the use of this information.
Statement of Vested Interest
Rounded Developments Enterprises Ltd are a well-recognised supplier of a range of sustainable building products and as such have a commercial interest in some of the recommendations contained within the report. In some cases, cost estimates have been given on the basis of current quotations for similar equipment supplied by Rounded Developments Enterprises Ltd, and may not be the only equipment available. However, it is our opinion that the study offers an appropriate level of detail in view of the resources available and information provided. The authors have no expectation of any order being placed with them and would welcome questioning of the choice and costs of any equipment.

Rendering older houses

External render finishes to solid walled buildings (esp. brick & stone)

Many of our homes are rendered, but most are not rendered using the right materials. Older houses (mostly made with solid walls of stone and brick) used breathable materials and lime mortars to bind them together. This system allows the walls to take moisture from the inside to the outside thanks to a number of factors:

1. The outer walls have a higher surface area (rougher texture) and this naturally means that they dry quicker and hence pull moisture through from the inside.

2. Houses have higher pressure inside than out, so air pressure also helps to push moisture through from the inside.

3. The materials used on the inside generally are less breathable than those on the outside, thus creating a gradient of breathability through the wall that attracts moisture to the outer part of the wall.

These characteristics mean that these walls will naturally keep the inner walls dry whilst allowing the outer walls to take the brunt of the weather. The outer walls will get soaked and absorb moisture, but will also dry out quickly as well. With the depth of these walls being between 22cm and 100cm this is no problem.

Over time construction practices, training and materials have changed and the pressure is now about using materials that are quick, convenient, easy and profitable. Material choice for most builders is not about choosing the right one through research, but about what they know. Our older terraces and buildings therefore get the same treatment as a more modern cavity walled house. This means the use of sand and cement for re-rendering.

The basic underpinning principle to this choice is that by using a water-proof render you keep the water out. Rising damp is then 'cured' by the installation of a chemical damp proofing course. Internal moisture is removed by mechanical ventilation and it is hoped that there is no water ingress from above (through leaky roofs, blocked gutters, worn felt etc.)

Unfortunately if any of these elements are compromised (cracks in the render, failure of the damp proof course etc) then water can get in, but not out again. So what happens? The walls get wet and wet walls = much higher thermal loss = cold spots = condensation = mould. Internal plaster gets soaked and paint starts to flake and peel off. So just by using the wrong materials we can change the house from a dry and active building into one that is cold, wet and in danger of structural damage.

Remedies

The remedy that is right for you will depend on a range of factors, including whether your home has already been rendered, what state of repair it is in, how exposed the house is to the elements and your financial ability to get it sorted.

1. With existing uncompromised cement render

If the render is not compromised and you have no problems with rising damp or water ingress from above and your home is well ventilated and heated then you are probably OK and need to do nothing (except hope that it stays this way)

2. With existing compromised cement render (but not 'blown')

If your render is cracked (and the really small cracks are the worst) and you have found evidence of damp in the house then you have two real choices:

a. repair the existing render and accept that the walls will be wet and cold for a while

b. bite the bullet and replace the render (see below for recommendation on type of render)

3. With existing 'blown' render that needs replacing

Once the render has blown is really is only doing harm to the building by trapping water. Hacking off the render should be easy, in fact you might find too much coming off at once, so be careful! Make good any poor bricks / stone etc and re-render using the following render:


Eco Home Centre recommends the following basic render mix:

Lime Putty (derived from limestone rather than chalk) mixed with a breathable aggregate (limestone dust for example).

This mix should be pumped onto the walls (to get more air into it - lime requires carbon dioxide to cure / set) and you might need to look at putting a hairy scratch coat on first or a webbed membrane.

This is the most breathable lime render you can get and so will act as a poultice to dry out your walls and hence keep them dry and efficient.

Top coats for lime based / breathable renders

The final finish is also very important. If you are using a lime putty render then you should use a limewash finish. This is effectively pure lime putty and so is even more porous than the render. This acts as a great 'wearing layer' for the render. Being so porous it will get saturated really quickly and will then shed water off of the surface when it is raining. When it stops raining it will pull the moisture through from the render and allow it to evaporate away. Limewash does need to be reapplied every so often (around 4-6 years) depending on exposure, but it is cheap.

For lime renders that are made from hydraulic lime or by using sand (not recommended by us) then you can use a silicate paint. These are really hard wearing and provide an excellent long lasting finish. Silicate paints are expensive, but provide value for money through being so long lived.

For guidance on builders / contractors who we feel understand these issues and are experienced in using and applying lime putty stone dust aggregate renders please contact the Eco Home Centre.


For more advice and products please call the Eco Home Centre on 02920373094.

Disclaimer

Rounded Developments Enterprises Ltd have endeavoured to ensure that the information contained in this report is accurate. However, Rounded Developments Enterprises Ltd. accepts no liability for the use of this information.

Statement of Vested Interest

Rounded Developments Enterprises Ltd are a well-recognised supplier of a range of sustainable building products and as such have a commercial interest in some of the recommendations contained within the report. In some cases, cost estimates have been given on the basis of current quotations for similar equipment supplied by Rounded Developments Enterprises Ltd, and may not be the only equipment available. However, it is our opinion that the study offers an appropriate level of detail in view of the resources available and information provided. The authors have no expectation of any order being placed with them and would welcome questioning of the choice and costs of any equipment.