can i use any polystyrene as insulation?

[phillbradley]

Hi,

I have recently brought a new house and there is insulation on the floor of the loft.

I wanted to know if I could insulate the roof section with normal polystyrene? I can get hold of old stuff from a photography company but just wanted to be use its not a fire hazard.

And if its not a fire hazard, what is a good way to attach the polystyrene between the rafters? it is only for storage so ascetics isn't an issue.

Thanks

 

[AronSearle]

I was under the impression that polystyrene used in buildings is fire treated (at least some of the products I've seen are), though I am not sure it's mandatory.

Normal polystyrene is quite flammable (and drips napalm like stuff), I am not aware there are rules against using it, but I wouldn't want it in my roof!

I think you also have to be careful about it touching electrical cables, ruins the wire coating or something.

 

[Ricardus]

You can actually buy polystyrene blocks specifically made for use as loft insulation from at least one of the big DIY chains, as well as wall veneer, ceiling tiles and coving out of the stuff so I guess the fire-risk has been reduced to an acceptable level.

But I would be cagey of using old, second hand packaging-type polystyrene to insulate your whole loft, just in case.

 

[phillbradley]

Ok, the quality of the stuff seems good but not worth the risk. Thanks for your comments. Think I'll do the good old fibre glass route!

 

[phillbradley]

Ok, the quality of the stuff seems good but not worth the risk. Thanks for your comments. Think I'll do the good old fibre glass route!

 

[mointainwalker]

The "risk" is very very small as the polystyrene is protected by the plasterboard (?) ceiling.

Fire-brigades don't like polystyrene ceiling-tiles as they catch fire and drip very quickly but in the loft is a lot better protected . There are no regs about using polystyrene in domestic settings.