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Tuesday, 20 December 2011

Draught proofing old (but potentially useful) chimneys

Many people have old chimneys that are not used any more. Central heating has done for the chimney what indoor bathrooms did for frozen bare bums. Our chimneys, though might just prove to be a useful and low carbon feature of housing in these austere times. The opportunity to burn wood as a source of secondary heating is just the ticket on those days where you just need a little bit of extra heat in the house to make it comfortable, or when you just need to heat one or two rooms.

The removal of a chimney and / or blocking it off completely therefore seems a bit rash (if it can be avoided). So how can we keep a chimney preserved for the future?

Well it still needs to be draught proofed, but more importantly it also needs to be covered to stop water ingress, the ubiquitous gulls from nesting on it and insects from living in it. So where many people turn to Chimney Balloons as an easy way of reducing the draughts associated with a chimney, we feel that this is the wrong approach. We recommend that you work your way down the chimney because if you start from the bottom it allows the top to get wet, nested on etc and this can cause more problems than it solves.

So for un-used chimneys why not fit a removable Chimney Cap. Eco Home sells the C-Cap (but there are others). This reduces the airflow dramatically, it also has an insect screen to stop little bugs from getting in and of course stops water from entering the chimney. It just clips over and so can be removed, if needed, at a later date. This means that you get to keep your chimney (just in case you want to re-use it in the future when fuel bills get too steep), but that you stop potential damage to it. Once the cap has been fitted then additional draught proofing can be undertaken lower down.

So start from the top and work downwards. If you do start from the bottom then you risk having a really damp chimney stack and this can let damp in that can appear anywhere down the flue line.

Letter box draughts

It does seem a bit strange that we fit lovely new well insulated doors and then put a draughty hole in them to collect (what is becoming more and more) a source of recycling stuff. Well apart from Christmas time I suppose when we tend to get more actual post than junk.

In foreign climes they have got around this by having a separate post box attached to the wall, thus saving on the post getting chewed by the pet and also from having a cold breeze blowing through the house in the winter. In Wales we are not there yet due to the mostly mild climate that we 'enjoy'. We are prepared to put up with worn brushes in our letter boxes, or just plain draughty ones that flap around in anything much past a breeze.

So does it need to be this way?

Well the lovely people at Ecoflap have developed a robust addition for your existing letter boxes. The Eco Flap is a simple system that actually blows itself shut, so the stronger the wind the more sealed it becomes! It also has a nifty system that allows for large items to be posted still, thus not incapacitating the functionality at all. So your insulated door can now become an insulated and draught proof door even with a letter box in it.

I gather from Eco Flap that they will also be bringing out a new petflap soon, so all you dog and cat owners can have an insulated and draught proof cat / door flap as well. Can't wait to try one myself.

Eco Flaps are available from Eco Home Centre in brown, black or white. For how to fit the Ecoflap check out this movie.

Thursday, 15 December 2011

Would being able to see refurbishments help you?

Eco Home Centre is looking to do some research on the needs behind refurbishment in Wales (and the UK). What we are proposing is a centre where people can come along and see how a range of properties have been refurbished in a sustainable manner (using appropriate low waste, non toxic and energy efficient products). The properties will have cut throughs to show how the work has been done and explanations on the key areas like window reveals.

Ideally we would like to refurbish a number of different types of property so that you will be able to find one that is similar to your own home. A guide would then be available to show you around to give you advice and guidance on the work and to offer a greater level of knowledge for your particular situation.

The 'show homes' would also be set up with sensors etc to record the performance of the building so that we can offer real life energy and water saving figures rather than generic ones (that are often over inflated).

So I would like some comments back from you as to whether this type of resource would be useful to you (and obviously it would be) and whether (more importantly) you would visit it (likely to be in South East Wales) and use it to its full potential. Please can you send me comments / suggestions etc so that I can bear these in mind when doing the research. Your comments will be most welcome.

Saturday, 10 December 2011

Bathroom art

We are researching some ideas on creating added value from waste that emanates from the refurbishment work associated with the Welsh Housing Quality Standard. Basically this is work that all the Social Landlords need to undertake to 'improve' the stock in Wales. This mostly translates to fitting new kitchens, bathrooms and boilers. So what to do with the old baths, sinks, kitchen units etc.

So what to do with an old bath?

Metal baths can be re-enamelled and then re-used - they are effectively as good as new.
Plastic baths can be repaired if necessary and re-used

However some are just not viable. Some are just the wrong colour and so the market is just not there, others are damaged beyond repair due to major cracks, chips etc. So what to do? Well an award winning idea is shown below.

Friday, 2 December 2011

Can visible mould and damp be good in a house?

Perhaps an odd question to ask, for how can visible mould and damp be healthy, beneficial or aesthetically pleasing?

The short answer is that it cannot, but there is a BUT. This BUT is quite a big one as well. Being able to see mould and damp at least tells you that there is a problem. Many houses these days are 'tarted up' to sell to un-supposing buyers who take out minimal structural or condition surveys. The main way of making a damp house look OK is to 'dry-line' it. This effectively places a piece of plasterboard between you and the damp wall. Lovely.

Knowing that you have damp, and where it is, can take you on a voyage of discovery, especially with older solid walled houses. You will discover how these houses were made and with what materials, it can also tell you how they were designed to work and how they coped with mould and damp in their long history. After all people of 100 years ago didn't want mould and damp either, so why has your house got it now?

Damp can have several causes and this article will help you to identify where it might be coming from, how to deal with it permanently and which materials to use so that you work with your home rather than against it.

To understand how these concepts and practices work, we first need to understand how these old solid walled houses worked originally. In North Wales, like many other parts of the country, people had to make buildings out of the local materials, so this meant a great deal of stone and slate was used to create walls and roofs. To bind it all together they used lime putty and a local aggregate (stone waste from quarries, sub-soil etc) The walls were either then left bare, or painted with a limewash (basically a watered down lime putty). The insides were rendered and plastered using a lime render (made from lime putty, local aggregates and some binder - sometimes horse hair, wool etc.) These materials were put together as a solid wall with dressed stone to the inside and out and any old rubble through in the middle as packing. These materials work together really well and they allow moisture to pass through them (either as a vapour or a liquid). The inside of the building was drier than than outside as the basic building physics meant that the water was attracted to the outer parts of the wall (issues to do with surface area of the wall, internal and external air pressure, internal temperatures etc.)

So these old houses basically kept the insides dry by allowing the water to move through them naturally. Yes they got wet when it rained, but the building physics and the thickness of the walls allowed this to happen in such a way that the building coped with it.

So what has gone wrong?

Time, does not stand still, and over the last few decades these old houses have been 'improved' using modern materials and techniques to accommodate new lifestyles. We now have central heating, better airtightness, inside toilets and bathrooms, double glazing, cookers and hobs rather than fires and chimneys and quite often concrete floors and wall renders. We have also been tempted into creating a modern feel to the house by using new smooth gypsum plasters and cheap oil derived paints and finishes.

These features have fundamentally changed the way that old buildings are used and this in turn has changed the pressure points on them. The materials that we now commonly use are also placing a new and largely unknown pressure on the house. The effect has been to radically change the way that they function as physical structures and this in turn has led to the mould and damp that we now commonly associate with old properties.

The new bathrooms and kitchens generate a huge amount of water vapour in the internal atmosphere. The removal of chimneys and the replacement doors and windows have radically reduced draughts (this is a good thing of course), but most importantly the use of cement renders, non breathing roof and wall insulation and the introduction of solid concrete floors has sealed the dampness in the house and especially the walls.

Where once water vapour and moisture passed through the structure, now it gets trapped behind impervious render. Where once air wicked away moisture from under the house, via air-vents under the floor, any rising damp is forced by the damp proof membranes into the walls (inc. internal walls). To make matters worse, the cement renders applied to the external walls, tend to crack over time as they don't flex like an old lime render. This lets water in behind the render and then stops it from getting out again. Where does it go? I think that you know the answer now.

To compound the problem, wet walls conduct heat better and this causes cold spots to form and this in turn is the breeding ground for mould. Cool and moist - lovely if you a mould spore!

So mould and damp can tell us that there is a problem and also show us where it is. This then allows us to do something about it. It could be: clearing out blocked guttering and drains; cracked render; rising damp from the floor; failed seals around doors and windows .... BUT at least you can then do something positive about it. If you don't know that there is a problem and it goes untreated it can cause structural failure in a house. Not what you want.

The best remedies are the old ones. By working with the house and using breathable materials (lime putty renders, wood fibre insulation, clay plasters, natural paints etc.) you can reinstate the way that it once worked and let the house do the hard work of keeping itself dry. If you are looking to buy a house just bear these things in mind - look out for: 'blown render' on the outside walls (it sounds hollow when you tap it); dry lined walls (again they sound hollow when tapped); worthless 20 year damp proof injection guarantees; flaky paint and rotting skirting. If in doubt buy a cheap damp meter and take along with you (note that dry lined properties will not appear damp to you or the meter, so a tap is essential).

If the house is fundamentally solid, but damp and mouldy, at least you will be going in with your eyes open and ready for the remedial work ahead.