Roof insulation

[crossy67]

Hopefully someone will be able to give a bit of advice on this one.

Is there any insulation that could be sprayed/pumped in between the rafters of our soon to be new house?  There are bedrooms in the loft with no insulation between their ceilings and the roof, I am just trying to think of am easy way of insulating them without either removing the roof or the ceilings.  Would it be possible to spray the same sort of thing you get in cavity wall insulation? 

[Quillan]

Well firstly it should be insulated and you should ask the builder why it is not. Perhaps he is leaving it till the last moment. I believe, someone will correct if I am wrong, that its mandatory in new builds. You can get 'spray foam' insulation but you must make sure its the fire retardant one. The only negative thing is if you want to install any extra light fittings as you will have to 'dig it out' where as more conventional types like Rockwell can easily be moved (cut even then rejoined) and put back when done.

[crossy67]

Sorry Q, I might have mislead you.   We are in the process of buying the house, it was built in 1920.  So there are spray systems that could be pumped between the rafters, that's good news.

Thanks.

[Richard51]

We had a similar problem with our old (and definitely uninsulated!) house.  The roof of the oldest part of the house was in a bad state of repair and needed replacing anyway so we insulated (to 12" thickness) at the same time.  The section of the house that didn't need re-roofing was more problematic as we couldn't put any insulation between the tiles and the ceilings if that insulation was likely to come into physical contact with the tiles.  (As it gets so cold in our bit of France, this could potentially cause cracking of the roof tiles.)   All our upstairs bedrooms are mansarded and with reasonably high ceilings, so we constructed a framework about a foot away from the internal wall / ceiling surfaces.  We packed the space it created with laine de verre and then boarded over and refinished.  The rooms are slightly smaller (but they were big to start off with) but are so much wamer - and our oil bill is a fraction of what it was pre-insulation.

Mrs R51

[Quillan]

If you don't want to loose to much space then and alternative is to use this very fine stuff made of between 20 to 30 layers which is compressed leaving a 'sandwich' of about 2 to 3 mm. Batten the ceiling with wood say 25mm square attach the insulation you seal the overlapped joints with tape then batten again using metal batten to which you can screw plasterboard to. Once the metal batten is installed but before you put up the plasterboard you have the opportunity of positioning lights if you wish. This stuff is mega efficient and is equivalent to about 10" of Rockwell insulation. If you search on the UK websites you will find the stuff and many of the Brico's in France sell the same.

[Chancer]

[quote user="Quillan"]. This stuff is mega efficient and is equivalent to about 10" of Rockwell insulation..[/quote]

But when you have the energy efficiency diagnostic to sell or rent it suddenly uses 100% of its efficiency [:(], in short the roof will be rated as uninsulated.

Guess what I have used [:(], I might be nice and warm working up in the grenier at the moment but it is cold comfort!