Response from English Housing Survey re: CWI

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In a previous blog entry I raised concerns that extraction of cavity wall insulation is not notifiable to building control and there is no agency counting the number of extractions.
It's very concerning that such records are not kept.  How can our governing bodies for energy and housing understand the scale of retrofit problems if the data are not there.

The fallback is the English(or other regional) Housing survey which is time lagged but if it accurately records the number of uninsulated houses then it may at least eventually highlight any concerning regress in number of insulated homes which could only be explained by older homes having their insulation removed.
My concern looking at the housing survey protocol was that it may mistake an extracted home with an insulated home as both could have the tell tale CWI pock marks which surveyors were told to look out for as evidence of CWI.

I sought clarification from the Ministry of Housing, Communities & Local Government who provided the following response:

Dear Mr xxx
Thank you for your enquiry dated 17 January 2019 regarding statistics of buildings with cavity wall insulation.
The EHS surveyors are trained to look for evidence of cavity wall insulation (CWI) in a number of different locations during the physical survey. Drill holes are only one such item of evidence. They will take all evidence into account before coming to a final judgement about the presence of CWI.
They do not directly collect evidence of CWI having been removed; but if they find such evidence that would inform their judgement about the presence of CWI, as this is based on the balance of evidence. They are also required to check with the householder if cavity wall insulation is present. If CWI had been extracted, and provided the householder was resident at the time, they would inform the surveyor of
this.
With thanks again for your time

Research Officer | English Housing Survey| Analysis and Data Directorate

So this confirms that there is no country wide record of CWI extractions but provides some hope that extraction is considered when recording the presence/absence of CWI in the survey.
Thank you to the EHS for providing this information.

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