Existing insulation and guarantee check across County Londonderry
We cover 4 towns in County Londonderry: Derry, Coleraine, Limavady and Magherafelt.
Every elevation is judged on its own exposure. Parts of County Londonderry 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.
Buyers and sellers in County Londonderry often book this check when a survey report or EPC raises questions about the walls. A survey in County Londonderry gives you facts before anyone drills: what the wall is, what is in the cavity and whether it is sound.
Building control in Northern Ireland
In Northern Ireland, inserting insulation into an existing cavity wall needs a building control application to your council before the work. We make sure the application route is agreed and confirmed in writing before any drilling starts.
Sources: Building Control NI: frequently asked questions; Belfast City Council: what are the building regulations.
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
- 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 County Londonderry
| Existing insulation and guarantee check guide prices | Guide 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 County Londonderry:
Tell us what is happening
Postcode, property type and what you have noticed.
Price agreed first
We confirm the price before anyone visits.
Visit and checks
Photos and readings at the areas that matter.
Findings in writing
What we found and the options, each priced separately.