Roofing

[Paul1919]

I have fibre glass insulation that keeps falling down from between the roof rafters.

It's a big roof. I want to staple a plastic vapour barrier over the top to prevent it falling.

My question is:

Should it be a vapour barrier. Or a permeable plastic covering.

 

[John D v2.0]

The fibreglass should be on the loft floor! If you really want a warm loft with "cold roof" construction, you would need a poly sheet on the warm side and good ventilation on the cold side to stop getting terrible condensation

 

[Paul1919]

Thanks John. There is insulation on the floor.
I have a problem with cluster flies getting in where the insulation has fallen.
I've used smoke diggers to kill them during the evening last week.
But I've a problem I've just noticed with bats. Lots of droppings which I'm about to remove.
I will block their entrance once I've found it

Paul

 

[^woody^]

Wont the bats eat the flies?

 

[Paul1919]

Maybe that's why they're there !
Gee that's just the sort of answer frequently found here. Unless it's two responders trading 'building regulation blows'

 

[Ian H]

By fibre glass do you mean the rock wool stuff that comes on a roll?

I dont think that's the best for between the rafters because you can't guarantee there will be an air gap behind it. You would be better dropping that to the floor and fitting a Celotex type insulation between the rafters, that would hold itself tight.