Jablite and cables

[pompeygit]

Kitchen area of house is single skin and will be battened and boarded with jablite as the insulation. New kitchen ring to be installed. Is 'Jablite' a proprietary name for polystyrene? Am worried about leeching of plasticiser...any advice? Anyone know the properties of Jablite?

 

[1john]

http://www.jablite.co.uk/ - expanded polystyrene.

You should be concerned about surrounding cables , especially on a ring final circuit, in insulation, it can make 2.5mm2 cable unsuitable in as much as it may not be able to carry 20A.

 

[flameport]

Jablite will damage the cables, so they will need to be protected using conduit.

Jablite is probably the wrong material to use here anyway - how thick is the insulation going to be?

 

[pompeygit]

Thanks for your input fellas. More info for you. It is a very narrow galley kitchen tacked onto the back of the house. Probably 150 years old. The builder proposes 1" jablite between battens and then a vapour barrier with plasterboard on top. The outside is currently rendered finish, then battened and slated. I must admit I am concerned as this arrangement doesnt allow 'breathing'. The wall will be covered with a breathable membrane before battens go on. But it looks like the jablite will be the same thickness as the battens, thus no air space. If you have an alternative idea please let me know and I will advise the builder and customer.

 

[flameport]

With only 1 inch of insulation, cutting a slot for conduit will remove almost all of the insulation, leaving cold lines where the cables are. These will inevitably attract condensation on the finished wall surface.

A single brick wall with 1 inch of polystyrene won't comply with building regulations for a habitable room anyway.