In this blog we will try to answer a question which seems to be relatively overlooked, is it legal to install polystyrene ceiling tiles in my house and what are the risks?
What are polystyrene ceiling tiles?
To answer this we need to look very briefly at what polystyrene actually is. Polystyrene is a derivative crude oil which is refined to create naphtha which is used in the production of plastics. It should be pointed out here that naphtha is flammable as are most products which are derived from crude oil. The type of polystyrene most people are accustomed with is often used in packing to protect the items inside. This is in fact expanded polystyrene where the brittle and otherwise rigid polystyrene is expanded with the use of a further flammable gas which is blown through the material to create the texture. The gas used to expand plastic dissipates relatively quickly although can be released during transportation and storage and in itself is a fire risk.
Polystyrene in its expanded form is a relatively effective insulator at low temperatures and so historically has been used on ceilings and wall uses in construction as well as within hidden voids to improve insulation generally. Therefore, polystyrene ceiling tiles have been used to both obscure uneven and poor surfaces by simply gluing them into place and to provide insulation.
Are polystyrene ceiling tiles illegal?
Put simply, no. This may of course change and the building regulations are updated regularly and so should be consulted. However at the time of writing this blog, polystyrene ceiling tiles and polystyrene construction products generally are not illegal.
Are polystyrene ceiling tiles a fire risk?
Yes. Unfortunately polystyrene will begin to soften at relatively high-temperatures approaching 100°C and at that point will begin to shrink. When heated further they will melt and at this point they give off a gaseous and flammable product. If exposed to further heat such as during a house fire, the gases will ignite. The products that are released during melting can also be highly toxic. This does of course the question as to why these products are allowed in construction without further precautionary measures to render them safe during fire.
It is therefore our recommendation that where polystyrene products are used and not shielded from fire such as behind plasterboard or within concealed and fire broken voids, they should be removed.
If you are concerned that your house contains these products, give us a call.