Maintenance Matters

Rhyd-y-car Terrace in St Fagans Museum of Welsh Life

For those, who have not been to St Fagans in Cardiff, it is worth the trip. Great place and an ideal way to start to understand how buildings have changed over time.

One of the key elements of the museum is Rhyd-y-car Terrace. It illustrates how one style of property (in this case a Welsh terrace of houses) has been altered over time to address the cultural needs / desires / aspirations of the residents. (click on the photo for a link to discover more)

The original terrace house is represented by the home on the left and the team has made alterations to each subsequent house to reflect the changes to terraces in Wales. So when you reach the last house it has a covering of render on the walls rather than limewash, tiles on the roof rather than slates, modern casement windows rather than sash, large window panes rather than small etc. The internal layouts and services have also changed. Fascinating, but intuitively we sort of know this. However, what is not really explained on site is whether these changes were positive or not.

Of course, we do not want to live in houses anymore that have open coal fires, draughty doors and windows etc. However, neither do we want to live in houses that suffer from trapped moisture in the walls, rotting timbers and poor internal air quality. Unfortunately, some of the 'improvements' that are illustrated in the terrace have caused problems like this in the real world.

In time you could add another cottage to this terrace, with its original stone walls now clad in polystyrene (EPS) external wall insulation. This is a reflection on where we are blindly heading without due regard for the original structure. Again we shall then have a warmer property that is at high risk of overheating and likely to suffer rot and mould issues from penetrative damp and condensation.

Designing improvements to buildings is important, but we must get it right. So again, I urge you to read the STBA documents and guidance on retrofit of older houses. See www.stbauk.org

However, this article is about maintenance. So where does this fit in with the retrofit agenda?

Well, when you read all the underpinning documents about retrofit, they all say that any building should be in a good state of repair and stable before any work starts. So before even contemplating any improvements the house should be damp free and well maintained.

This is where much of the trouble has started. Organisations like the Government have targeted their initial efforts on those properties that were in urgent need and these tend to be the ones in a poor state of repair. So they started putting a load of retrofit measures on properties that weren't ready for it. Putting a load of non-breathable cladding / insulation over a wet wall, just seals in the damp. This would be bad enough, but putting a load of non-breathable cladding / insulation over a wet wall badly so that more water can get in, well, you can guess what has been happening!

So, we need to ensure that our buildings are in a good state of repair first and then we need to ensure that we do any retrofit works well. The second element is starting to be addressed (slowly and still with little real knowledge of the characteristics and pathology of traditionally built houses), but the issues of maintenance is less attractive to business.

Large companies delivering large scale projects are not really interested in minor works, or leaving buildings to become stable over time before starting with the big tools and toys. They just need to crack on, come rain or shine, cold or heat and get the job done ASAP and as cheaply as possible.

So we need to take a step back. Assess what we have, understand it, fix it, let it settle and become stable and then start to improve it sensitively and with the right amount of care and caution so that we don't mess it up.

So the first rung on this retrofit / improvement ladder for traditional buildings is not EPS wall insulation, it is Maintenance and Building Pathology.

CADW have produced some guidance on maintenance, but people see this as being for conservation areas and heritage buildings. We need to make maintenance relevant to the 34% of buildings in Wales that are traditionally built. This means all the terraces and stone / solid brick built homes that litter the landscape that we are so familiar with and proud of. After all it is these buildings that define the character of our inner cities and valleys.

Maintenance in itself is relevant to the retrofit agenda. A wet wall is 1/3 less efficient than a dry wall for example.

Building pathology is equally important. The recent Each Home Counts report for the UK Government highlights the recent case in Preston where the race for energy efficiency and the lack of understanding of older houses has left a trail of catastrophe. The details are being repressed by those concerned inc the Government as it really is a tale of woe, but suffice to say the underpinning issue was the lack of knowledge on traditional buildings within the mainstream construction and retrofit industry.

So we need to understand our homes, their history, how they work. This means getting to grip with material science and building dynamics. A good surveyor should be able to tell you these things, but most just refer on to 'specialists'. Unfortunately most of these are not really specialists, just glorified sales people. So we need 'Power to the People'. These are your homes and you are the ones paying for works to be done. So I urge you to understand older buildings and look after them well. Most of the things that I see when visiting homes are simple maintenance issues that can solve many ills.

As a starter for ten, have a think about the following:

A hole in the junction between a window and a sill. Water running down the window above the hole will go into it. What then? Well generally a damp patch and potentially a rotten floor joist. Solution? Fill the hole with some silicon sealer. Cost? 10p in silicon? 10 minutes in time. Potential savings? £350 for a damp report, £1,000 for DPC injection and replacement plaster, £2,000 for replacement joists,....

A crack in render on a west facing wall. Water above the crack will flow down into it. It cannot get back out if it is a modern cement render. So a damp patch. Rotten timbers maybe... Solution. Fill the crack. Cost? DIY solution, maybe £10. Contractor, maybe £100. Potential savings? Well, see above.

Dislodged guttering pouring water down and into a wall. Replacement bracket cost, maybe £1. Cost of leaving it? Easily into the £1,000's of pounds.

So check things like seals around doors and windows, leaf build up in the gutters, cracks in render, mortar and stonework. Make sure external ground levels are kept 15cm below internal floor levels, that extracts are working properly, that floor vents are not blocked by litter and dirt, that pipes through the wall are sealed up properly, that slipped tiles are replaced quickly, chimney stacks are in a good state and that any repairs are made with lime mortars etc etc.

I could go on. But I hope that you get the message. Preventative maintenance is cheap, relatively easy and essential both in terms of keeping you and your home healthy both now and into the future.

Beware the "Damp Meter"

This is the tool of choice for damp proofing companies

The Protimeter is pretty much ubiquitous in the damp and building surveying world. The meter is used to show owners how damp their homes are. This is also invariably 'rising' damp that 'will require' an injected DPC. However, is this tool an actual damp meter?

The short answer is NO!

These meters measure electrical resistance between the two prongs. That is not necessarily the same as the amount of water between them. Originally they were developed for timber to check how dry it was. In timber the only real thing that will conduct electricity is water and hence they were quite useful. However, this is not the case in masonry.

So what else could they be measuring?

Well, there is another factor that can give a high readings on a protimeter:

Carbon content. As you may be aware some old mortars were made using dust from industrial waste. This is especially true in areas like Cardiff where we have black mortar. This mortar is high in carbon and hence conducts electricity well. So high readings may well be to do with the mortar, not moisture.

So, if you have a high reading in a house without old mortar / plaster, then a high reading is probably indicative of dampness. However, the key question is then; What is causing the Damp?

Well this opens up a range of options (however, the majority of the damp industry only looks for 'moisture' along the base of ground floor walls).

The damp could be caused by:

Hygroscopic salts. These are actually very common in walls and are often the cause of high readings. Salts can be introduced by the building process, water ingress and from the combustion processes associated with fireplaces. So if you have high readings around the base of the fire place / hearth this may well be salts not rising damp. The salts are 'hygroscopic' and that means that they attract moisture to them. So this moisture might be linked to condensation, being located in high humidity areas like kitchens / bathrooms, etc. So the moisture is probably associated with salt not 'rising damp'. So just keep dusting off the salt residues until they disappear and lo and behold you will have cured the damp. Simple.

Condensation. Virtually all external walls have a cold bridge along their base and this attracts moisture to condense there. This is natural and nothing really to worry about unless it is causing some mould issues. This condensation can also be caused by a lack of ventilation. So again you might need to look at ventilation / insulation rather than jump straight into a potentially unnecessary damp proof course. Note that thermal bridging can occur in a number of other places (ceiling edges, around window frames etc) where the wall is cold for some reason so again check issues like insulation cover and building defects.

Leaks. Old or current leaks can show up on the meters, so this is a case of fixing the cause, or just allowing the wall to dry naturally.

Material incompatibility. Old houses have walls that allow moisture to pass through them, however most modern materials are designed to resist moisture movement. Commonly you get a combination of materials that don't like each other in terms of moisture and a lot of problems stem from this. Gypsum plaster is particularly prone to becoming hygroscopic when it has been placed over old lime plaster.

Penetrating damp. This is the likely cause of most damp issues. The industry tends to recommend injecting more DPCs into the wall rather than addressing the actual problem. This tends to be simple and cheap maintenance issues like sealing around windows, cracked render, repointing etc.

So if you see a 'damp' meter, make sure it is attached to something that has an inquisitive brain and also nothing to sell you!!

Forget Energy Efficiency think Health!

Readers of this blog will know my views on lots of the energy driven 'improvements' that we are blindly doing in the UK at the moment.

We are making so many mistakes due to the fact that we are using more than useless techniques, materials etc in a slap dash manner. All of this is being done with the best intentions, but we are storing up many problems for the future by our haste and lack of underpinning knowledge.

In years to come we shall look back at this period in our history and hang our heads in shame, I think that in the worse case scenarios it will be regarded as a modern day 'asbestos' story.

So how can we change and do this better?

Well, a very easy way would be to think about it all in a very different manner.

At the moment all we can think about is energy bills, carbon reduction, fuel poverty and regeneration. None of these things are bad, but they do drive us into solutions that are not fit for purpose. For any readers not up to speed here there are fundamental flaws with how we measure energy efficiency in buildings (especially older ones), how we measure thermal efficiency in walls and also more importantly how awful we are when it comes to moisture. Have a look at the STBA reports on thermal and moisture measuring for more info.

Now DECC know all of this stuff - the STBA have told them, but it takes a long time to change Standards, Conventions, a whole industry! And then there is the political fallout! So basically we will have to wait a long time before we manage to make things better, so in the meantime we shall continue to make lots of mistakes and install lots of inappropriate measures.

So, as a proposal, should we not think about Health.

To have a healthy internal environment we need to provide:

• Fresh clean air
• Stable Relative Humidity (around 50-60%)
• No mould or damp
• Comfortable internal temperatures that are not prone to overheating
• Sufficient natural light
• Low toxicity in materials
• No off-gassing from materials
• A long term solution that maintains these conditions

To do this we need to have items like:

• Breathable walls (where they were designed to breathe)
• Insulation that is suitable
• Good ventilation that is controlled by Internal Air Quality systems
• Natural materials used
• Low / Non toxic materials used
• Good quality installers / builders

So the basic idea is that, if we can create safe, comfortable and healthy internal environments then energy efficiency comes as a by-product of this process / specification. So we would create good internal environments that are suitable for human beings. Isn't this the point of a building in the first place - to create a safe, sheltered and nice place to spend time with loved ones?

Won't it be great to look at a building and think 'how can I make this a really great place to live?' The satisfaction in making a house a home that you would want to live in and enjoy. After all someone has to live there and shouldn't we make it as healthy, homely and safe as possible?

However if we work within our current unrealistically blinkered parameters we shall just produce internal environments that help to burden the NHS and also provide people with poor quality of domestic life.

So lets start to put people first and I wouldn't mind betting that we shall be able to not only provide high quality space, but also save more money in the long term and reduce CO2.

Wales is in an ideal place to make this happen, but we need to drop using dangerous tools like rdSAP and also BS5250, especially for older buildings.

New eco-products give hope!

The Dutch Postcode Lottery and Cradle to Cradle competitions have had some amazing finalists this year.

The winner this year's Postcode Lottery Green Challenge was BioMason’s CO₂-free brick production process, which uses bacteria to ‘grow’ bricks! Can't wait to see these around, especially given the amount of embodied energy in a conventional brick.

The other finalists in the American Cradle to Cradle competition include:

• Mushroom^R Insulation – a green replacement for plastic foams, which combines agricultural byproducts with fungal mycelium to ‘grow’ structural rigid insulation
• Bellwether Materials’ Softbatts – sheep’s wool insulation
• GR Green Building Products’ Green Cedar^TM and Green Slate^TM – synthetic roofing and cladding materials made from waste limestone and recycled plastic milk bottles and shopping bags
• Dutch Design Initiative’s reinforced wood wool cement board (pdf link)
• Ecococon’s straw panels
• Haplobuilt’s Haploblocks – a small scale prefabricated building system (pdf link)
• Ecor^R Universal Construction Panels made using waste cellulose fibre.

Great to see such a wide range of ideas being brought forward to help reduce our embodied energy associated with new builds, extensions and also some refurbishment.

Inside out: the wrong way round

When we move into a new house we tend to do two things:

1. Complete the work detailed in the mortgage agreement (this tends to be things like damp proof courses, underpinning, roof repairs);
2. Decorate in order to make your mark on your new property.

So what you are left with is a nice looking internal environment and a structure that a finance institution is happy with.

There are some issues with this.

1. Firstly, finance companies do not understand the workings of older solid walled properties and so many of their recommendations are pointless / potentially damaging. The money spent on these measures could / should be better used using more permanent solutions, but this is a huge topic that is impossible to deal with in this short post.

2. Decorating over issues like mould, damp, cracks is pretty pointless unless the root cause is also dealt with. I have seen this over and over again where people have spent a lot of time and money making their mark only to find that the mould / damp / cracks re-appear. This is the point of this post.

We would recommend using those initially tight resources to solve the problems with the house. These issues are not limited to what the mortgage company says, so don't be lured into a false sense of security. Use this blog to flush out some potential problems (the indicators are things like dry lining, freshly painted walls etc.)

Most of these issues tend to be on the outside of the house, hence the title of the post! The majority of what needs to be done to a house, in order to make it fault free, is based in chronic poor external maintenance. So have a good look at things like:

• Re-pointing
• Cracked / blown renders
• Raised ground levels
• Blocked vents
• Blocked / broken / faulty guttering
• Rotten timbers
• Flashing around chimneys
• Chimneys not protected from rainwater
• Silicon failure around doors and windows
• Incorrect paint being used on solid walls
• Poorly sealed walls around incoming / out-going services

Once the outside of the house has been maintained properly then you can decorate to your hearts content with the knowledge that it will not fail in a few months time.

Remember that in order to keep your house looking good and operating well you will need to use the correct materials and products. Reading this blog will help with that. Also it is worth noting that maintenance is a regular requirement and not just a one off. So every now and again have a good once-around the outside of the house to ensure that all is well; it is easy for guttering to get blocked / fail and for new cracks to appear in cement render, etc.

CADW have a really good website on maintenance. Don't be fooled by the term 'historic', as this applies to all solid walled buildings. See http://www.maintenancematterswales.org/

Are 'Eco' paints all the same?

The simple answer is No!

Unfortunately 'Green' paint can be full of 'green wash'. Some paints are seen as eco, just because they are water based. Others are labelled as green because they have reduced the energy used in the production of the paint. Others have reduced their VOC levels and see this as being acceptable to market a product as eco-friendly.

The factors that rock your boat might be satisfied by this, however many people are effectively being duped into buying an 'eco' paint when really the credentials that underpin the product are quite questionable.

The real factors that should underpin choice of an eco-paint are (we think):

• Production methods (use of renewable energy in production, local ingredients, etc.)
• Use of low impact natural materials
• Long lasting and high quality finish
• Healthy to apply and live with
• Local production / efficient distribution network
• No use / minimal use of finite petro-chemical based ingredients

I think that the most important factor is to get a paint that works right for you. So if you have a breathable wall structure you will need a breathable paint. If you are painting a hallway you may well want a scrubbable paint, etc.

There are proper eco paints that can do this, but it is dependent on their ingredients. For example, Green Paints are made with soya oils and these dry to be really hard and hence scrubbable. Earthborn Clay Paints are made of clay and this is really breathable and hence brilliant for lime rendered walls. Auro paints are made from linseed and citrus oils, certified VOC free, and are great if you want something that is high quality and behaves in a manner that is really similar to conventional emulsions.

To try and make all of this a bit easier the Eco Home Centre developed an Eco Paint Chooser. This allows you to get the right paint for your home and for you also to choose from other important factors like VOC free, Made in the UK, etc.