How Much Does Loft Insulation Cost in the UK? 2026 Price Guide

Most UK homeowners pay about £650 to £1,200 to have loft insulation professionally installed in 2026, depending on the size of the loft and the material. DIY mineral wool starts at around £300.

That pays for itself quickly: a typical home saves roughly £200 to £380 a year on heating, so most jobs pay back in about 3 to 4 years. This guide breaks down the price by house type and material, what pushes the cost up, and whether you can get it free. Prices are guides only; every loft is different.

Quick answer: loft insulation cost in 2026

• Terraced house: about £650 professionally fitted

• Semi-detached house: about £825

• Detached house or bungalow: about £1,200

• DIY mineral wool: from about £300–£500 for the materials

• Grant-funded: free for some eligible households (see the grants section)

Prices are for topping up to the recommended 270mm depth with mineral wool. Ask for a free quote for a fixed price on your own loft.

Loft insulation cost by house type

The bigger the loft, the more material and time it needs, so price rises with house size. A detached house costs roughly double a terrace.

House type	Professional cost (270mm mineral wool)	Typical saving per year	Payback
Terraced	£654	£200	about 3.3 years
Semi-detached	£825	£230	about 3.6 years
Detached	£1,206	£380	about 3.2 years

A bungalow is priced like a detached house (about £1,206) because the loft covers the whole footprint. Costs, savings and paybacks are guides: payback is the price divided by the yearly saving, and real savings depend on your heating and how much insulation you already have.

Loft insulation cost per m² by material

Mineral wool is the cheapest material at about £5 to £10 per m², while spray foam is the most expensive at £35 to £50 per m². Prices below are the material and fitting rate per square metre.

Material	Cost per m²	Best for
Mineral wool blanket (rolls)	£5–£10	Standard lofts with clear joists; best value
Recycled glass wool (e.g. Knauf Loft Roll 44)	£5–£10 fitted; rolls alone about £2.80–£5.70	Low-cost eco option, made from recycled glass bottles
Loose-fill / blown	£8–£12	Awkward, cramped or irregular spaces
Thermal foil layer	about £14	Extra layer over existing insulation
Sheep's wool (e.g. Thermafleece CosyWool)	about £16 for the rolls alone at 100mm, before fitting	Natural, breathable, low-carbon; premium price
PIR insulation boards	£30–£35	Rafters and room-in-roof, where depth is limited
Spray foam	£35–£50	Airtightness; harder to remove later

Recycled glass wool and sheep's wool prices are for the rolls only, based on supplier prices in July 2026 (100mm to 200mm for glass wool, 100mm for sheep's wool), so fitting is extra. Sheep's wool costs several times more than mineral wool per m², and reaching 270mm needs more layers, so your quote will be higher. In return you get a natural, breathable product with a lower carbon footprint.

Whichever you choose, aim for 270mm depth, the current recommendation for mineral wool. Some lenders and surveyors are cautious about spray foam on roof timbers, so check with them before choosing it.

What affects the cost of loft insulation

Loft size and material set the base price, but five other things can move your quote up or down.

• Existing insulation. Topping up an old layer is cheaper than starting from bare joists, because less material is needed.

• Access. A small hatch, low roof pitch or a boarded loft adds labour time. Labour is typically around £250 per day.

• Removal of old insulation. Damp, contaminated or compressed insulation may need to come out first, which adds to the bill.

• Extras. Pipe insulation (£6 to £35 per metre), a water tank jacket (about £150), rerouting electrical cables (about £250 to £300 per day) and loft boarding (about £55 per m²) are usually priced separately.

• Ventilation and condition. Eaves ventilation must stay clear so the roof timbers can breathe. Fixing this, or treating damp, is best done at the same time.

A fixed-price quote after a quick loft survey avoids surprises.

Can you get free loft insulation in 2026?

Some low-income households in Greater Manchester can get loft insulation fully funded, but the national schemes have changed this year. The Great British Insulation Scheme required installations to be complete by 31 March 2026, so treat any offer that still quotes it with caution.

Today the main routes are:

• Warm Homes Local Grant (Greater Manchester). Loft insulation is a covered measure, and owner-occupiers can get 100% funding, up to £30,000 in total across all measures. You may qualify if you live in one of the most deprived income areas, receive a means-tested benefit, meet the ECO4 Flex criteria, or have a combined household income below £36,000. Owner-occupied homes need an EPC rating of D to G; private rentals need D or E (F or G with a registered exemption). Apply through the Greater Manchester Combined Authority (GMCA) Retrofit Portal.

• Warm Homes Plan. The government has said it will offer fully funded insulation for low-income households and low-interest loans for other homeowners. Details are still developing, so check GOV.UK for the latest.

• Local help in Oldham. Oldham Council points residents to Groundwork Green Doctors (free home energy audits) and the National Energy Action Oldham Energy Action Team on 0161 543 0000 for free energy advice and retrofit consultations.

Door-to-door offers of "free" insulation deserve caution. Use only installers you can check, and get any grant-funded work confirmed in writing.

Not eligible? A standard top-up to 270mm typically costs less than £1,200 and pays back within a few years, so it is still one of the cheapest energy upgrades you can make.

DIY vs professional installation

DIY saves about half the cost, but a professional finish is faster and avoids the mistakes that waste the savings.

	DIY	Professional
Typical cost	£300–£500 for materials	£500–£1,200 fitted
Time	A weekend, plus cleaning up	Usually half a day to a day
Risks	Compressed or gappy insulation, blocked eaves vents, covered downlights and cables	Surveyed first, fitted to depth and ventilation kept clear
Best for	Simple, clear, easy-access lofts	Awkward lofts, old insulation, boarding and ladders

Mineral wool rolls are the easiest DIY job. If you also want to store things up there, keep boards above the insulation on a raised frame so it is never squashed; see our loft boarding service. A loft hatch and loft ladder can be fitted in the same visit, which is usually cheaper than booking separately.

Is loft insulation worth it? Yes. With a typical yearly saving of £200 to £380, the cost is earned back in around three to four years, and insulation can last more than 40 years if kept dry. It also helps your EPC rating, which matters when you sell or let.

Get a loft insulation quote in Oldham and Greater Manchester

Ecofriendly Lofts is based in Royton, Oldham and covers Oldham and Greater Manchester. We offer a free estimate, advise on the depth your loft needs and use eco-friendly materials such as sheep's wool and recycled glass wool.

• Free estimate for your loft

• Advice on depth, ventilation and hatch upgrades

• Optional boarding, hatch and ladder in the same visit

Call 01613 992975 or 07825 534172, email info@ecofriendlylofts.com, or request your free quote.

Loft insulation cost FAQs

How much does loft insulation cost in the UK?

Professional loft insulation typically costs between £500 and £1,200 in 2026, depending on the size of your loft and the material. DIY with mineral wool starts at around £300 to £500 for materials.

How much does it cost to insulate a semi-detached house loft?

About £825 for a professional top-up to 270mm with mineral wool. A terraced house is around £650 and a detached house around £1,200.

How much does loft insulation cost per m²?

Mineral wool costs about £5 to £10 per m², loose-fill £8 to £12, PIR boards £30 to £35 and spray foam £35 to £50.

Is loft insulation worth the money?

Yes. A typical home saves roughly £200 to £380 a year, so the cost is usually recovered in three to four years.

Can I get free loft insulation?

Yes, eligible Greater Manchester households can get loft insulation fully funded through the Warm Homes Local Grant, applied for via the GMCA Retrofit Portal. Eligibility depends on your income or benefits and your home's EPC rating.

How thick should loft insulation be?

Building regulations recommend at least 270mm of mineral wool insulation.

Can I insulate my loft myself?

Yes, mineral wool rolls are a common DIY job. Take care not to block eaves ventilation or compress the insulation, and use a professional for awkward lofts.

How long does loft insulation last?

Well-installed insulation can last over 40 years if it stays dry and is not compressed.