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Northolt · Greater London

Existing insulation and guarantee check in Northolt

For properties in Northolt, an insulation and guarantee check starts with a clear price and ends with a written record of what was found and done. 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 Northolt

Covering Northolt and the UB5 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 Northolt properties

We cover Northolt and the UB5 postcode district, including nearby Greenford, Harrow and Southall. It is about 11 miles west of London.

Every inspection point in Northolt is photographed and logged, so you have a record to show a buyer, lender or contractor. The written result for your Northolt property is plain English: what we found, what it means and what, if anything, to do next.

Before any material is chosen, exposure is checked. 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.

For regulations, if cavity wall insulation follows in Northolt, 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 Northolt

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

Guide prices for Northolt

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 Northolt:

  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 Northolt: questions

Is there VAT on an insulation and guarantee check in Northolt?

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.

Do you work on rented homes in Northolt?

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

How soon can you visit in Northolt?

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.

How much does an insulation and guarantee check cost in Northolt?

Guide prices are shown on this page, and the price for your Northolt property is confirmed before you book.

Nearby towns

Book an insulation check in Northolt

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