Internal wall insulation · England
Internal wall insulation in Wiltshire
Planning internal wall insulation anywhere in Wiltshire? We cover towns including Swindon and Salisbury, and check planning and building control for each address. We plan internal insulation in Wiltshire homes room by room so you keep the rest of the house usable.
- Free survey and fixed written price
- Guide price from £75 per m² 0% VAT
- Planning and building control checked for England
Free survey in Wiltshire
Tell us the postcode and what you need.
Included as standard
- Loses roughly 50–100mm per insulated wall
- Keeps the outside of the house exactly as it is
- Can be done one room at a time during a renovation
- Sockets, radiators, skirting and coving are moved and refitted
- Needs careful detailing at floor joists, reveals and corners
Wiltshire: walls, weather and approvals
The South West has many stone and solid-walled cottages, exposed coastal properties and a share of post-war system-built houses, including types such as the Cornish Unit.
Exposure to wind-driven rain varies across Wiltshire: sheltered town streets fare better than walls on high ground or facing the prevailing weather, and the render, beads and cill details are chosen with that in mind.
For terraced homes in Wiltshire with attractive brick fronts, one approach is to insulate the front internally and the rear externally.
- Nation
- England
- Region
- South West
- Towns covered
- Swindon, Salisbury, Trowbridge, Chippenham
- Guide price
- From £75 per m² 0% VAT
England: planning and regulations
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.
Renovating more than half of a wall's area — insulating it, or stripping and re-rendering it — or more than a quarter of the building's whole external envelope brings in the energy requirements of Part L, so building control needs to be involved and the wall should reach about 0.30 W/m²K where that's technically, functionally and economically feasible.
Do I need Building Regulations approval?
Yes, in England and Wales once you insulate or replaster more than half of a wall's area (or more than a quarter of the building's whole envelope), it's treated as renovating a thermal element. The wall should reach about 0.30 W/m²K where practical, and building control needs to be involved.
Internal wall insulation prices in Wiltshire
| 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.
What happens next
Get a guide price
Try the online quote tool for a ballpark figure.
Book the survey
A visit at a time that suits you.
Agree the quote
Nothing starts until you've signed the written price.
We do the work
Planned around weather, with you kept informed.
Internal wall insulation in Wiltshire: 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.
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.
How much room space will I lose?
Usually 50–100mm on each insulated wall, depending on the system.
Do you cover all of Wiltshire?
Yes. We survey and quote internal wall insulation across Wiltshire, including Swindon, Salisbury, Trowbridge, Chippenham.
Do I need planning permission in England?
For houses, external wall insulation and render are often permitted development where the finish looks similar to the existing walls. We check your address before quoting.