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Caernarfon · Gwynedd

Existing insulation and guarantee check in Caernarfon

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. In Caernarfon the visit is priced up front, and any follow-on work is quoted separately so you can choose.

Book an insulation check in Caernarfon

Covering Caernarfon and the LL55 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 Caernarfon properties

Caernarfon is among the towns we cover in Gwynedd, alongside Bangor, Porthmadog and Holyhead. It is about 6 miles south-west of Bangor.

Buyers and sellers in Caernarfon often book this check when a survey report or EPC raises questions about the walls. Where a Caernarfon wall shows cold patches or damp, the survey targets those areas first rather than sampling at random.

Every elevation is judged on its own exposure. Parts of Gwynedd face some of the heaviest wind-driven rain in the UK, especially exposed coastal and upland sites. Here the survey is stricter: some walls suit only certain certified systems, and some should not be filled at all.

On compliance, if cavity wall insulation follows in Caernarfon, filling a cavity is notifiable work under the Building Regulations as they apply in Wales, usually self-certified through a competent person scheme.

Rules in Wales

Filling a cavity is notifiable work under the Building Regulations as they apply in Wales, usually self-certified through a competent person scheme if insulation work follows.

Sources: Welsh Government: building work competent person schemes; 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 Caernarfon

  • Guidance on tracing a guarantee
  • Short written report
  • Borescope checks
  • Damp signs inside and out

Guide prices for Caernarfon

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.

What happens next for a Caernarfon property:

  1. Get in touch

    Online, by phone or WhatsApp.

  2. Your price

    Confirmed in writing before you book.

  3. The visit

    Carried out at an agreed time, with photos of what we find.

  4. Your report

    Plain English, with any follow-on work quoted separately.

Last reviewed 19 October 2026.

Existing insulation and guarantee check in Caernarfon: questions

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

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.

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.

Do you work on rented homes in Caernarfon?

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

How soon can you visit in Caernarfon?

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.

Nearby towns

Book an insulation check in Caernarfon

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