Loft insulation top-up in Gwynedd
Homes and buildings across Gwynedd can book a loft insulation top-up, starting with a free survey and a fixed written quote.
That includes Bangor (Gwynedd), Caernarfon, Dolgellau, Holyhead and Llangefni, and the villages around them.
Where we work around Gwynedd
We work across the Gwynedd and Isle of Anglesey council areas.
That covers the LL postcode areas.
| Councils | Gwynedd and Isle of Anglesey |
|---|---|
| Postcode areas | LL |
| Towns listed | 7 |
What is a loft insulation top-up?
Before we quote we measure the existing layer in several places and check its condition. If it is dry, even and not contaminated, we keep it and lay the top-up across it at right angles. More about a loft insulation top-up.
- Tank jacket and pipe lagging in the loft
- Eaves ventilation kept clear
- Depth check and photos before and after
Why book with us in Gwynedd
No pressure selling
You get everything in writing and decide in your own time.
Clear contact details
Your quote says who to call with questions before, during and after the work.
Eaves kept clear
Insulation is held back from the eaves so the loft can still ventilate.
Fixed written price
The price on the quote is the price you pay. It only changes if you change the job, or if we find something hidden, such as rot, and you agree the change in writing first.
How much does a loft insulation top-up cost in Gwynedd?
Installing insulation in a home is zero-rated for VAT until 31 March 2027 and 5% after that, under HMRC's rules for energy-saving materials (notice 708/6). The Energy Saving Trust puts a typical professionally installed loft at about £750 from bare joists, or £600 to top up from 120 mm.
Building regulations in Wales
Wales has its own Approved Document L. Insulation alone is not normally notified, but conversions need building control. How the rules work across the UK.
Funding in Wales
- Warm Homes Nest, run for the Welsh Government, offers free improvements to eligible low-income households.
- ECO4, the energy supplier scheme, runs until 31 December 2026 for eligible households.
- Check Nest's eligibility checker before agreeing to any funded offer.
Questions about a loft insulation top-up in Gwynedd
Do you cover the whole of Gwynedd?
Yes. We cover every town and village in Gwynedd, including Bangor (Gwynedd), Caernarfon and Dolgellau.
Which council covers my address in Gwynedd?
Councils in Gwynedd include Gwynedd and Isle of Anglesey. Your council matters for building control questions and some funding schemes.
Can new insulation go on top of old insulation?
Yes, if the old layer is dry, clean and reasonably even. If it is damp, contaminated or badly compressed we recommend removing it first.
Is it worth topping up 100 mm of loft insulation?
Often, if the existing layer is in good condition and you also want a warmer house or a better EPC. On bill savings alone, a top-up from about 100 mm takes decades to pay back, so the case is strongest when it is done alongside other loft work.
