Insulating walls internally.

BISHI

We have a small 2 storey extension on the back of our victorian house - it is long and thin and consequently has a massive surface area to volume ratio and haemorrhages in the cold. The lodger who used this room is moving out so we want to take the opportunity to make this part of the house more efficient - we're going to replace the old double glazing and want to make the walls keep more heat in - any recommendations would be great.
Also - which first - windows or walls - or doesn't it matter..?

noiseboy72

Is there a cavity wall you can fill, or is it a solid skin ? Cavity wall insulation has a massive effect, so do this first. If you don't have a cavity, foil lined insulation can be applied to the wall, but be careful about fire regulations and condensation build up.

Eliminate any draughts and fit better loft insulation- you should have at least 12" depth. Modern radiators are also more efficient, so should keep the bills down.

Either that, or move in a polar bear to replace the lodger!

Gerbil

Might be worth looking at this guys approach on The Register.

He used aerogel based dry lining to mimimize the amount of space he lost internally. Since you say the space is long and thin I guess you don't want to lose any more space internally

BISHI

I am assuming the loft space is already insulated as any snow that settles on it does not melt until that on the main roof does.It is a very shallow pitch and has no access hatch. I have looked at the width of the wall and it is definately more than 2 bricks thick - but not that much thicker so I have assumed the space for cavity wall insulation is negligible. Thinking about it, it could be breeze block and brick thick without a gap - I guess a hole needs drilling to check !!!

BISHI

Looks interesting............. but way way too expensive..!

dianbolden

The least expensive way to insulate your home from the inside that I can think of is through the use of a fluffy layer of fiber glass. This can be a little labor intensive but if you got spare time, I'm sure you can finish it right away. You will just need to cut the fiber glass as the wall requires and stick it into place. I would suggest you go for the largest size of fiber glass so that you won't have to cut that much. The best tools to have is a utility knife and a straightedge.

As for me, I insulated the walls before the windows simply because it has a huge surface area to cover. Hope this helps.

- Dian B.

johntheexpat

Isolant mince multicouche 17 Novostrat - CASTORAMA

Isolation des murs | Le Guide des matériaux d'isolation » Le guide de l'isolation des murs et toitures

Vetry popular in France.  Ideal for placing behind dry lined walls and apparently can be as effective as 250mm of rockwool.  Its about an inch thick for a 25 layer variety.

malcolmv24

Although not as effective as a good layer of insulation Wallrock Thermal Liner which can be bought in 2 thickness's can be applied to internal wall and will reduce heating up times by about 65% and heat loss by 15%