We have recently had Arbed2 ERDF external wall insulation work carried out on our house. The document specifying work to be carried out by the installer states that horizontal mineral wool fire breaks are to be fitted in the wall cavity between floors, and a vertical firebreak between properties.
Theses have not been fitted – I am wondering if you know if whether this is a legal requirement or not?


Jason Watkins

  • You must to post comments

Ah yes, I see what you mean. Were the two houses that burnt down externally clad/insulated? Because I was thinking that in the original construction there is a gap between the party wall and the steel cladding upstairs or the render downstairs, but as neither are combustible the risk of fire spread there is probably lower as both are non-combustible.

This is a problem with a lot of houses. Near here a Victorian terraced house burnt down and as there was no fire break in the loft at all, the upstairs of both houses next to it burnt out too.

  • Jason Watkins

    Yes they had been externally clad, exactly as our has been. The fire started downstairs in the corner nearest the party wall at the front of the house. And without firebreaks between floors or houses spread through cavity very quickly. Its quite worrying.

  • You must to post comments

Thanks for replying Ed.

We do have a party wall.
The contractors have put 19mm ply on the outside of houses to which they fix the polystyrene external wall insulation panels. But between the ply and the internal wall there is a cavity that runs between the houses without a fire break!!
A fire started in a house down the street and the fire spread so quickly between the houses that the families only just got out. Both families lost everything and houses had to be leveled back to the foundation.
I think I will ask our local fire department for their views.

Thanks again.

  • You must to post comments

Hi, I can’t answer the legal aspect, but a firebreak between houses has been standard since long before BISF houses were built. Typically they have a party wall made of a double layer of concrete blocks from the foundations up to the floor of the loft and then a single layer of the same from there to the roof. This acts as a firebreak and also for security and soundproofing.


  • You must to post comments
Showing 3 results
Your Answer
Guest Author
Post as a guest by filling out the fields below or if you already have an account.
Image Upload
Upload your image here
File Name Size
There are currently no files uploaded.
Maximum file size 1MB.
Supported file formats: gif jpeg jpg png