Insulation & Breathability

[MatthewC]

Aside from the apparent toxic fumes at the time, could this prove to be a better long term solution for those houses that have never had their cavities filled? Technically it's no different to Celotex.

Cavity foam is VERY different to Celotex. I bought a new house in 1981 and this had cavity foam insulation injected. After a few months dampness started appearing inside the walls and this was explained as water being transmitted through the walls by the foam. Celotex has a metallic covering and so cannot do this.

 

[agbagb]

The damp chill just seems to hang around in the atmosphere--no visible mould or moisture anywhere------/quote]

Hi Jocelyn,

That gives clue as to what the problem might be. It could be all down to how the air is convecting around the house. A single source of heat downstairs can set up very strong convection currents around the house. There will be a stream of heat rising at one point of the stairwell, then cooling against walls and ceiling forming a cold stream spilling down at another point. In between, at any point, can be dead areas with air that is hardly mixing, just spinning around causing the "damp chill hanging around".

With a thermometer, (or cold hands) close to the walls, stair well opening, at ceiling height, at floor level, you can start to get a feel of what is happening.
To prove if strong convection is a problem, try positioning a desk fan where it can disrupt the natural currents. eg. half way down the stairs, to mix the flows.

Longer term solutions are a bit harder, but turbulence and slowing the flows will be key. Partly open doors (instead of wide open), strategically placed pictures with chunky frames on the cold flow walls might tip the balance without having to resort to ceiling fans or extra insulation, or more diverse heating.

Andy

 

[jocelyn plummer]

Hi Andy---wow, you have made me think---- yes, 2 sources of warmth downstairs-- Aga city 60 on 24/7 in kitchen, (end of hall opposite front door), log burner in the living room evenings only November until a couple of weeks ago ( the living room runs the length of the property and has one door off the hall way. But, and this is interesting-I keep all 3 bedroom doors wide open to give the landing maximum light from each window as we are mid terrace, i did this on the assumption that heat rises and would warm the bedrooms. The bathroom has an electric towel rail. There is a principal residence on one side of us--- she told me that her house is warmer now than in the past when ours was a second home and not used much. The other side of us is a rarely used second home left totally unheated. A heating engineer did say to me that we would be best off having a storage heater in the hall to sort out the cold spot, so I suppose that ties in with what you are saying/. Oddly I do have pictures all up the stairwell one of which is a heavy gilt framed oil painting covering most of the wall.

 

[malcolm]

If you have a gas supply available I should go for central heating. It is marvellous - my grandfather's rheumatism went away when he had it installed. It makes the whole house toasty without having to bother about insulation.

You need to get to a better standard of insulation than your average 1980s house to heat it comfortably if the only heat sources are downstairs. It will get cold upstairs because the heat is being sucked out from upstairs faster then it can get in. It is possible to heat the house comfortably from only downstairs so long as the upstairs is insulated very much more than downstairs. Thick loft insulation, double glazing upstairs, wall insulation (not cavity as it very often creates a thermal bridge which makes it colder) are worth trying. Drying anything upstairs will make it worse as evaporation soaks heat away and the moisture goes into the walls and reduces their thermal efficiency.