Building control and cavity wall insulation

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When CWI is put in, the installer must notify building control of the insulation. And that's about it.
When you sell your property the application date and presence of CWI will show up on building regulation searches initiated by the potential buyer's solicitor.

Building control have no record of the type of insulation and the search does not tell you which company installed it. If you do need to get CWI removed, then it's not clear how this would work. Should building control make a record of the removal?

In my area local authority building control is provided by Southern Building Control Partnership so I though I would ask them about what happens when it is removed. My main worry was that somehow that we would be forced to replace it with a different type of insulation.

I spoke to a chap who to be honest wasn't at all helpful.
He told me that building regulations inspectors would only have to be involved if 25% or more of the bricks in the external leaf would have to be removed. If there was any doubt then he told me to put an application in for review by building regs.
He asked me how I was intending to remove the CWI and I said that I'd approached some extraction companies but there was no best practice or 'industry standard' for extraction which makes it difficult. He told me that they don't get involved and that the whole industry is essentially unregulated.

I asked him if his department had ever been involved in extraction of cavity wall insulation and he said not in the 30 years he's been working there.
I informed him of my investigation into the cavity width being less than 50mm which is against building regs and he said that he didn't know the finer detail of such things.
His only real suggestion was to use a tile on baton cladding which was popular in the area to which I responded that it would not really be in keeping with an art deco style house.

Anyway, It sounds like they don't have much knowledge or interest because it's not part of their workload - the 'experts' are the self regulated installers and infrastructure.

I will chase this up again when the CWI is removed because I do want the building control searches from a potential house buyer to be an issue many years down the line.



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