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Northampton · Northamptonshire

Existing insulation and guarantee check in Northampton

Need an insulation and guarantee check in Northampton? You get the price first, then a visit, then the findings in plain English. 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 Northampton

Covering Northampton and the NN1 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 Northampton properties

Northampton sits in Northamptonshire. We work across the NN1 district, including nearby Wellingborough, Daventry and Rushden.

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

Local weather affects which walls can be filled. Much of Northamptonshire 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.

In terms of approvals, if cavity wall insulation follows in Northampton, 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 Northampton

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

Guide prices for Northampton

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 Northampton:

  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 Northampton: questions

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

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

Do you work on rented homes in Northampton?

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

Do you cold-call in Northampton?

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

Do you cover Northampton?

Yes. Northampton and the NN1 postcode district are within our Northamptonshire coverage, along with nearby Wellingborough and Daventry.

Nearby towns

Book an insulation check in Northampton

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