Foiled

[BoyElectric]

I'm planning to insulate part of the loft floor - under an area to be boarded - with Kingspan tp10.

Does it make any difference whether I use the foiled stuff or not? Which is better for this purpose?

 

[Deluks]

Probably very little difference, can you even get kspan unfoiled?

 

[noseall]

the foil acts a a vapour barrier.

it may be significant particularly if the existing ceiling plasterboards are plain backed. any joins would need to be taped with foil tape also.

 

[BoyElectric]

Not sure whether they do unfoiled. Maybe I was looking at something else.

You don't lay a vapour barrier with normal loft insulation, so I guess my question is whether or not the vapour barrier will cause problems with condensation in the rooms below? Basically is foil backed urethane a bad choice of product for this purpose?

 

[noseall]

a vapour barrier at loft ceiling level is to prevent moist air entering the loft from habitable rooms below.

 

[Deluks]

As he's only doing part of, and not all the ceiling, surely it's a moot point?

Many lath and plaster ceiling about with no VB

 

[noseall]

As he's only doing part of, and not all the ceiling, surely it's a moot point?

Many lath and plaster ceiling about with no VB

indeed Deluks indeed.

i see it as a step in the right direction.

but as you say, there is no point in making a silk purse out or a sows ear.

 

[^woody^]

The foil adds to the insulation value of the board, and is not there as a vapour barrier - but does forms one

 

[Deluks]

but as you say, there is no point in making a silk purse out of a sows ear.

Where did I say that? YOU SWINE!!!

 

[noseall]

but as you say, there is no point in making a silk purse out of a sows ear.

Where did I say that? YOU SWINE!!!

oink?