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Durham · County Durham

Existing insulation and guarantee check in Durham

Existing insulation and guarantee check in Durham is priced before you book, and what we find is written up with photos. An existing insulation check tells you whether a cavity is filled, what with, whether it looks dry and intact, and how to trace any guarantee.

Book an insulation check in Durham

Covering Durham and the DH1 district. Tell us about the property. We confirm the price before you book.

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We use your details only to answer this enquiry and arrange your visit, sharing them only with the registered installer we appoint for your job and the providers named in our privacy notice. No marketing lists, no cold calls.

Existing insulation and guarantee check for Durham properties

Durham is among the towns we cover in County Durham, alongside Chester-le-Street, Stanley and Bishop Auckland. Durham is one of the main towns we cover in County Durham.

The written result for your Durham property is plain English: what we found, what it means and what, if anything, to do next. Buyers and sellers in Durham often book this check when a survey report or EPC raises questions about the walls.

Local weather affects which walls can be filled. County Durham has a mix of moderate and more exposed sites. Hilltop, coastal and west-facing walls take the brunt of wind-driven rain, so the survey records exposure for each elevation before a material is chosen.

On the rules side, if cavity wall insulation follows in Durham, filling a cavity is notifiable building work and needs a building notice or competent-person self-certification.

Rules in England

Filling a cavity is notifiable building work and needs a building notice or competent-person self-certification if insulation work follows.

Sources: Planning Portal: cavity wall insulation and building regulations; CIGA: CWISC competent person scheme.

How to tell if a house already has cavity insulation

Look for a regular pattern of small patched holes in the mortar joints, often about a metre apart. Check the EPC, which may say 'filled cavity'. Ask the seller for a guarantee. The reliable answer is a borescope check, because patched holes can be from a fill that was later removed and EPCs are sometimes wrong.

What is included in Durham

  • Short written report
  • Visual check of walls and patched holes
  • Guidance on tracing a guarantee
  • Borescope checks

Guide prices for Durham

Existing insulation and guarantee check guide prices
Existing insulation and guarantee check guide pricesGuide price
Existing insulation and guarantee check£145–£245

This work is not insulation, so it is normally standard-rated for VAT. Guide prices include VAT where it applies. Guide ranges only: the fixed price is confirmed in writing before any work starts, and anything that could not be seen at survey is agreed with you first.

How it works in Durham:

  1. Tell us what is happening

    Postcode, property type and what you have noticed.

  2. Price agreed first

    We confirm the price before anyone visits.

  3. Visit and checks

    Photos and readings at the areas that matter.

  4. Findings in writing

    What we found and the options, each priced separately.

Last reviewed 19 October 2026.

Existing insulation and guarantee check in Durham: questions

Will you tell me if I do not need any work?

Yes. If the findings show nothing needs doing, or a cheaper fix such as clearing a gutter will do, we say so.

How soon can you visit in Durham?

We arrange dates when you get in touch. Availability varies through the year, so we give you real dates rather than a promise on the website.

Do you cover Durham?

Yes. Durham and the DH1 postcode district are within our County Durham coverage, along with nearby Chester-le-Street and Stanley.

Do you cold-call in Durham?

No. We only come out when you have asked us to. If someone cold-calls offering free insulation, check before you agree to anything.

Nearby towns

Book an insulation check in Durham

Priced before you book. Findings in writing. No cold calls.