Loft insulation grants 2026
ECO4, the Warm Homes: Local Grant and what's closed – plus why there's no funding for spray foam removal.
Old, flattened, damp or contaminated loft insulation removed and replaced with mineral wool to the recommended 270mm, in line with current Building Regulations guidance. Top ups available where your existing insulation is still sound.
Energy efficiency standards for homes in England are set out in Approved Document L (Conservation of fuel and power). For existing homes, the current edition sets a U-value of 0.16 W/m²K when a roof is renovated or upgraded – the lower the U-value, the less heat escapes.
In practice, for a typical cold loft insulated at ceiling (joist) level, the Energy Saving Trust recommends a minimum of 270mm of mineral wool, laid in two layers: one between the joists and a second at right angles across them. That generally achieves the 0.16 W/m²K figure.
Many older homes still have 100mm or less – the standard when they were built – and decades later that insulation is often compressed or patchy.
Do I need Building Control? Simply laying insulation in a loft doesn't usually need notifying, but where it forms part of a wider renovation, conversion or roof replacement, Approved Document L standards apply. If we think your project may need approval, we'll tell you and suggest you check with your local Building Control. More in our loft insulation Building Regulations guide.
Less heat escapes through the roof, so rooms stay warmer for longer.
Reducing heat loss cuts the energy needed to heat your home.
Loft insulation is one of the measures assessed on an Energy Performance Certificate.
Removing damp or contaminated material gets rid of mould, odours and pest debris.
We measure the current depth and check condition, ventilation, wiring, pipes and tanks, and look for damp, pests or vermiculite.
We recommend a top up or full replacement and explain why, with a clear written price.
Dust sheets on access routes and around the loft hatch to keep your home clean.
Old insulation is bagged up in the loft and removed from site by us as a registered waste carrier, and the loft is cleared of debris.
Mineral wool laid between and across the joists to 270mm, with eaves vents kept clear and cables lifted clear of the insulation where possible.
Pipes and cold water tanks insulated (leaving the area directly under the tank uninsulated), and the loft hatch insulated and draught-proofed. Finally, you receive a completion report with photos of every stage of the work.
If your existing insulation is dry, clean and evenly laid but just not deep enough, a loft insulation top up is usually the quickest, most cost-effective upgrade. We lay an extra layer of mineral wool across the joists to bring the total depth up to the recommended 270mm.
If we find damp, contamination or compression during the survey, we'll tell you – putting new insulation on top of a problem only hides it.
Whether it's a top up or a full replacement, we photograph every stage and give you a completion report, so you can see the job has been done properly.
If we're removing spray foam from between your rafters, we can insulate at ceiling level afterwards so your home stays warm and the roof can ventilate properly – one team, one job.
Commercial building or rental portfolio? See commercial roof spaces.
We install, replace and top up loft insulation for homes in Salisbury and across Wiltshire, including Swindon, Chippenham, Trowbridge, Devizes, Warminster, Marlborough, Amesbury, Melksham and Calne, and in parts of Dorset and Somerset by arrangement. See all areas we cover.
Sources: Approved Document L, Volume 1: Dwellings (2021 edition incorporating 2023 amendments), Tables 4.2 and 4.3; Energy Saving Trust – Roof and loft insulation.
Genuine reviews left by our customers on independent trade sites. Ratings as shown on each platform in October 2026 – click through to read every review.
“From quote to the job being finished very happy with Ollie and the team, they completed the work in two days, very clean tidy and polite…”
“Ollie arrived and gave the estimate for the replacement of loft insulation, once we accepted the estimate the work was carried out very quickly and with little fuss on the two hottest days of this year.”
“Ollie was very quick to respond to my enquiry, after he reviewed the photos he was able to quote and managed to do the job over the weekend. Excellent job and great price, would highly recommend”
Plain-English guides, with sources, to help you make the right decision. See all guides.
ECO4, the Warm Homes: Local Grant and what's closed – plus why there's no funding for spray foam removal.
Part L, U-values and the 270mm guideline explained, and when Building Control applies.
The Energy Saving Trust recommends a minimum of 270mm of mineral wool insulation for a typical loft. Other materials perform differently, so the depth needed varies by product.
The Great British Insulation Scheme closed on 31 March 2026 and ECO4 ends on 31 December 2026. In England, low-income households may still qualify for the council-run Warm Homes: Local Grant. See our loft insulation grants guide for the details.
Approved Document L (Volume 1: Dwellings, 2021 edition incorporating 2023 amendments) sets a U-value of 0.16 W/m²K when a roof is renovated or upgraded in an existing home, and 0.15 W/m²K for new roof elements in existing homes. For a typical cold loft insulated at joist level, around 270mm of mineral wool generally achieves 0.16 W/m²K.
If your existing insulation is dry, clean and evenly laid, a top up to 270mm is usually the most cost-effective option. If it's damp, mouldy, contaminated by pests, badly compressed or patchy, it should be removed and replaced – laying new insulation over it won't fix the problem.
Common reasons include damp or water damage from roof leaks, rodent or bird contamination, insulation flattened by storage, smoke or fire damage, or needing clear access for roof, electrical or conversion work.
Vermiculite is a loose, pebble-like insulation found in some older homes, and some vermiculite may contain asbestos. We won't disturb it until it has been tested. If asbestos is suspected, it must be dealt with by a suitably licensed specialist.
Yes, but storage shouldn't squash the insulation, because compressed insulation works less well. Raised loft boarding on legs lets you store items above the full 270mm depth.
Insulating at joist level makes the loft space above colder, so good ventilation matters. We keep eaves ventilation clear and look for signs of condensation as part of the job.
Yes. We photograph every stage of every job, and when the work is finished you receive a completion report showing each stage of the work in progress – so you can see it has been done properly. You can share it with your surveyor, buyer or lender if they ask for evidence of the work.
We're based in Salisbury and install loft insulation across Wiltshire, including Swindon, Chippenham, Trowbridge, Devizes, Warminster, Marlborough, Amesbury, Melksham and Calne, and in parts of Dorset and Somerset by arrangement.
Free, no-obligation quotes across Salisbury, Wiltshire, Dorset and Somerset. Call 07415 173934.