Internal wall insulation · Wales
Internal wall insulation in Dyfed
Get guide prices online, then a free survey and fixed quote for internal wall insulation in Dyfed, including Ammanford and Carmarthen. Where a property in Dyfed is in a conservation area or the front elevation must stay unchanged, internal insulation is often the practical route.
- Free survey and fixed written price
- Guide price from £75 per m² 0% VAT
- Planning and building control checked for Wales
Free survey in Dyfed
Tell us the postcode and what you need.
What the job covers
- Keeps the outside of the house exactly as it is
- Needs careful detailing at floor joists, reveals and corners
- Insulated plasterboard, stud wall or breathable systems
- Sockets, radiators, skirting and coving are moved and refitted
- Loses roughly 50–100mm per insulated wall
What we look for in Dyfed
West Wales has a high share of older solid-walled and stone homes, many in exposed coastal or rural settings.
Parts of Dyfed fall in the higher wind-driven rain exposure bands, especially coastal and upland sites, so render specification, movement joints and detailing at cills, verges and the base of the wall matter more than usual.
Where a property in Dyfed is in a conservation area or the front elevation must stay unchanged, internal insulation is often the practical route.
- Nation
- Wales
- Region
- West Wales
- Towns covered
- Llanelli, Ammanford, Carmarthen, Aberystwyth, Milford Haven, Haverfordwest
- Guide price
- From £75 per m² 0% VAT
Planning and building control in Wales
Internal insulation rarely needs planning permission, but in England and Wales insulating or replastering more than half of a wall's area involves building control, and listed buildings need consent for internal changes that affect their character.
The Building Regulations as they apply in Wales treat insulating or re-rendering more than half of a wall's area, or more than a quarter of the building's whole envelope, as renovating a thermal element, with Approved Document L (Wales) setting the target. Building control is involved before work starts.
What are the risks with internal insulation?
Insulating inside makes the masonry colder, so moisture risk rises. Weak points are where floor joists bear into the wall, window reveals and corners. A condensation risk check for the build-up, a continuous vapour control layer where specified, and returning insulation into reveals deal with most of it.
Internal wall insulation prices in Dyfed
| Item | Guide price | Notes |
|---|---|---|
| Insulated plasterboard, supplied and skimmed | £75–£110 per m²0% VAT | |
| Insulated stud wall | £90–£130 per m²0% VAT | |
| Typical bedroom, one external wall | £1,795–£2,9950% VAT | Including making good |
Confirmed by a fixed written quote after survey. 0% VAT: installing insulation in a home is zero-rated until 31 March 2027, so these figures are the total; 5% applies from 1 April 2027.
From enquiry to finished wall
Tell us about the property
Use the quote tool or form, or call. Photos help.
Free survey
We measure, check the walls and confirm approvals.
Fixed written quote
System, details, access, exclusions and VAT in writing.
Installation
Scheduled for suitable weather, with a clear programme.
Internal wall insulation in Dyfed: questions
Is internal insulation cheaper than external?
Per m² usually yes, but the cost of moving fittings and redecorating narrows the gap on whole-house jobs.
How much room space will I lose?
Usually 50–100mm on each insulated wall, depending on the system.
What happens to my radiators and sockets?
They're taken off and refitted on the new wall face. Electrical work is done by a qualified electrician.
Do you cover all of Dyfed?
Yes. We survey and quote internal wall insulation across Dyfed, including Llanelli, Ammanford, Carmarthen, Aberystwyth, Milford Haven.
Do I need planning permission in Wales?
Permitted development rules for houses in Wales are similar to England's: a similar-appearance finish on a house is often permitted, while conservation areas, National Parks, Areas of Outstanding Natural Beauty, flats, commercial buildings and listed buildings need permission or consent. We check your address before quoting.