Loft insulation myths and scams

Myth 1: “Everyone can get free loft insulation”

Every free route in 2026 is means-tested or targeted. ECO4 needs a qualifying benefit or a council LA Flex referral (for example household income under £31,000), plus the right EPC band. England’s Warm Homes: Local Grant usually needs household income of £36,000 or less. Scotland, Wales and Northern Ireland have their own tests. An advert that promises free loft insulation to every homeowner is wrong, whatever the small print says. Our who qualifies page has the real gates.

Myth 2: “Apply now for the Great British Insulation Scheme”

The Great British Insulation Scheme was the one recent route that qualified homes by council tax band without a means test. It ended on 31 March 2026, and GOV.UK’s eligibility service now shows a closure notice. Old web pages and adverts still use it. Any invitation to apply for GBIS now is out of date, and a firm still using it is not keeping up with the rules.

Myth 3: “You will save £590 a year”

That figure circulates widely. The Energy Saving Trust’s current figures (updated May 2026, July 2026 fuel prices) for insulating a bare loft in Great Britain range from £140 a year for a mid-terrace to £360 for a detached house. For a loft that already has 120mm, the saving is £13 to £35 a year. A saving quoted without saying which house type and which starting depth it assumes should be treated with suspicion.

Myth 4: “Your insulation no longer meets regulations and must come out”

The Energy Saving Trust records this exact claim as misinformation some installers have used to increase sales, usually to sell spray foam. Dry, clean mineral wool can stay where it is and be topped up. See spray foam problems.

Myth 5: “300mm is the legal minimum”

The Energy Saving Trust gives 270mm as the building regulations recommendation for mineral wool. Northern Ireland’s Affordable Warmth Scheme specifies loft insulation installed or topped up to 300mm. Neither makes a sound 270mm layer illegal or in need of replacing.

Myth 6: “ECO4 is free, full stop”

ECO4 is usually free for eligible households, but Ofgem says it is not a grant scheme, different suppliers may offer different levels of support, and in some cases you may be asked to contribute. Ask before you agree, and get the answer in writing.

How to check an offer in five minutes

1. Ask the caller three questions: which scheme, which energy supplier or council is funding it, and the installer’s company name.
2. Check the installer on the TrustMark register and ask which Competent Person Scheme they belong to.
3. Contact the supplier or council yourself, using details from their own website, not the number the caller gives you. GOV.UK recommends exactly this if you are unsure.
4. Check the scheme against our schemes page: is it open, and do you meet its rules?
5. Never pay anything on the doorstep and never sign on the first visit.

If something has already gone wrong

If you are unhappy with work done under a government scheme, GOV.UK says to contact the installer or the company that guaranteed the work, and Citizens Advice if they do not resolve it. Keep every document: the quote, the pre-existing loft declaration, the guarantee and any photos of the loft before and after. The EST suggests taking before-and-after photos of any professional job for exactly this reason.