0800 088 6248
CavityWallInsulationUKCAVITYWALLINSULATIONUK.CO.UK
Cavity wall insulationCavity wall suitability surveyCavity wall insulation removalCavity insulation top-upDamp investigation after cavity insulationBonded polystyrene bead insulationBlown mineral wool insulationParty wall cavity insulationBorescope cavity inspectionCavity wall insulation for landlordsGrant and funding checkLoft insulation
Greater London · England

Existing insulation and guarantee check in Greater London

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. Our Greater London coverage includes London, Islington, Bexley and the towns around them.

Old cavity insulation drill holes, filled with mortar, spaced across a brick wall

Book an insulation check in Greater London

Tell us about the property. We confirm the price before you book.

Enter a UK postcode.
Choose a service.
Enter your name.
Enter a phone number with at least 10 digits.
Enter a valid email address.

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 across Greater London

We cover 81 towns in Greater London, including London, Islington, Bexley, Barking, Archway and more.

Local weather affects which walls can be filled. Much of Greater London sits in the more sheltered driving-rain zones of the UK, which widens the choice of fill. Exposed elevations, coastal sites and high ground still get checked wall by wall.

Buyers and sellers in Greater London often book this check when a survey report or EPC raises questions about the walls. A survey in Greater London gives you facts before anyone drills: what the wall is, what is in the cavity and whether it is sound.

Building Regulations in England

Filling an existing cavity wall is notifiable building work in England. Either a building notice goes to building control before the work, or the installer self-certifies it through a government-approved competent person scheme such as CIGA's CWISC scheme. The insulation used must also be suitable for the wall it goes into, which is why the survey checks construction, condition and exposure first.

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

Tracing a guarantee

Many cavity fills carry a 25-year guarantee from the Cavity Insulation Guarantee Agency (CIGA). CIGA can confirm whether a property is covered and can issue a duplicate guarantee for a fee; at the time of writing that fee is £60 including VAT, and proof of ownership is required.

What is included

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

Existing insulation and guarantee check prices in Greater London

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.

The steps for an insulation and guarantee check in Greater London:

  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 Greater London: questions

Do you cover all of Greater London?

Yes. We cover 81 towns across Greater London, including London, Islington, Bexley and Barking, and the villages around them. Island and remote addresses are surveyed by arrangement.

Do you work on rented homes in Greater London?

Yes. Landlords and agents in Greater London can book batch visits, and work is arranged around tenants.

Do you cold-call in Greater London?

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

Is there VAT on an insulation and guarantee check in Greater London?

Existing insulation and guarantee check is not insulation, so it is normally charged at the standard rate of VAT. The VAT treatment is confirmed on your quote.

Existing insulation and guarantee check in nearby areas

Book an insulation check in Greater London

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