Builders
Carpenters
Electricians
Flooring Specialists
Gardeners
Handymen
Heating Engineers
Painters & Decorators
Plasterers & Renderers
Plumbers
Roofers
Tilers
myLoft Insulation Cost
At a Glance
- The cost to insulate a loft typically runs between £700 and £1,200.
- Most loft insulation jobs take 1 day or less to complete.
- A breakdown of loft insulation costs in 2026, plus the main factors that affect prices.
- How long the job takes, what's involved, and advice from tradespeople on MyJobQuote.
- How to find and hire a local loft insulation specialist.
Get free estimates
Are you a trade? Get more work today!
£950
Table of Contents
- How Much Does Loft Insulation Cost?
- Labour Costs and Timescales
- What Affects Loft Insulation Costs?
- Additional Costs for Loft Insulation
- Topping Up Existing Loft Insulation
- How Much Can Loft Insulation Save on Energy Bills?
- Types of Loft Insulation
- What's Involved in Installing Loft Insulation?
- Spray Foam Insulation
- Can I Insulate a Loft Myself?
- Building Regulations for Loft Insulation
- Can I Get a Grant for Loft Insulation?
- Removing Old Loft Insulation
- Checklist: Finding a Loft Insulation Contractor
- FAQs
Loft Insulation Cost Calculator
How Much Does Loft Insulation Cost?
In 2026, loft insulation costs between £700 and £1,200 for a typical home.
The cost depends on the size of the loft, the material chosen, and whether the insulation is being installed from scratch or topped up. For a 3-bedroom semi-detached house — the most common type of job — the average installed cost in 2026 is around £930.
This guide covers loft floor insulation specifically. If you're looking to insulate at roof level instead, see our roof insulation cost guide. If you're also looking to board the loft for storage, see our loft boarding cost guide.
Loft Insulation Cost by Property Type
The table below shows typical installed costs to insulate a loft to the UK-recommended depth of 270mm using standard mineral wool, by house type:
| Property Type | Typical Cost |
|---|---|
| Flat or 1-bedroom apartment | £200–£500 |
| 2-bedroom terrace | £300–£700 |
| 3-bedroom semi-detached | £500–£1,200 |
| 4-bedroom detached | £900–£1,800 |
| Period property (pre-1919) | £1,200–£2,500 |
Want a custom price?
Post your job
Period properties attract a premium due to non-standard joist depths, breathability requirements, and the additional care needed during installation.
Loft Insulation Cost by Material (Per 15m²)
The table below shows average installed costs to insulate 15m² of loft floor using common materials. Materials-only prices are lower — most installers quote supply and fit.
| Type of Insulation | Average Cost (15m²) |
|---|---|
| Blanket (mineral wool rolls) | £400–£600 |
| Loose-fill | £275–£325 |
| Blown (injected) | £400–£500 |
Want a custom price?
Post your job
Current UK building regulations recommend a minimum depth of 270mm for loft insulation. How much material is needed depends on the type chosen and the size of the loft.
Labour Costs and Timescales
Loft insulation installers typically charge £150 to £250 per day, with higher rates in London and the South East. Most standard jobs are completed within a single day, though the method you choose affects how long it takes.
| Method | Typical Duration | Typical Labour Cost |
|---|---|---|
| Loose-fill or blown (machine-applied) | 1–4 hours | Often priced per m² or flat fee |
| Blanket rolls (standard loft) | 1 day | £150–£250 |
| Full installation with boarding | 2–3 days | £300–£750 |
Want a custom price?
Post your job
Small insulation-only jobs are often priced per m² or as a flat fee rather than a day rate. A minimum charge may apply for very small areas.
What Affects Loft Insulation Costs?
- Property size — A larger loft requires more material and more installation time, increasing the overall cost.
- Material choice — Blanket rolls are cost-effective for most jobs. Loose-fill suits awkward or irregular spaces. Blown insulation speeds up installation in hard-to-reach areas but requires specialist equipment.
- Depth and coverage — Meeting the recommended 270mm depth and insulating around obstructions (tanks, pipes, cabling) adds time and material cost.
- Top-up vs. full installation — If existing insulation is in reasonable condition, topping it up to the recommended depth is cheaper than a full replacement.
- Access — Tight hatches, limited headroom, or a difficult loft layout slow down the work and may attract additional labour charges.
- Labour charges — Day rates of £150 to £250 are typical. London and South East rates tend to be higher.
- Extras — Adding raised loft legs, vapour control layers, or eaves vents will increase the overall price.
Additional Costs for Loft Insulation
These optional extras and situational add-ons can increase the total price. Use the ranges below as a guide — your quote will reflect access conditions, layout, and any remedial work required.
| Item | Typical Cost | Notes |
|---|---|---|
| Loft boarding (raised system) | £80–£100 per m² | If you want storage access after insulating. |
| Loft legs (raised boarding system) | £10–£18 per m² | Required when boarding over insulation to avoid compression. |
| Tank and pipe insulation (lagging) | £60–£180 | Insulating a cold loft increases freezing risk for any tanks or pipes left unlagged. |
| Vapour control layer or eaves vents | £50–£150 | Helps manage condensation and maintain airflow at the eaves. |
| Electrical safety adjustments | £80–£250 | Rerouting cables, downlight guards, and safe clearances from insulation. |
| Old insulation removal and disposal | £250–£400 | Needed if existing insulation is damaged, damp, or incorrectly fitted. |
| Spray foam removal | £40 per m² (average) | Required if spray foam is present and affecting mortgageability. |
| Pest or damp remediation | £120–£400 | Must be resolved before new insulation is installed. |
| Small-job minimum or access surcharge | £40–£120 | Applied for very small areas or difficult access. |
Want a custom price for your loft?
Post your job
Once a loft is properly insulated, the space above the ceiling runs colder — which increases the risk of pipes and water tanks freezing. Always ask your installer about lagging as part of the same visit.
Topping Up Existing Loft Insulation
Many UK homes already have some loft insulation but fall short of the recommended 270mm depth. In these cases, topping up the existing layer is usually cheaper than a full replacement — and just as effective, provided the existing insulation is dry and undamaged.
A top-up job typically costs between £400 and £900 for a standard semi-detached home, depending on how much material needs to be added and the size of the loft. A professional can assess the existing depth and condition before quoting.
If the existing insulation is damp, compressed, or pest-damaged, full removal and replacement will be needed instead.
How Much Can Loft Insulation Save on Energy Bills?
Insulating an uninsulated loft to the recommended 270mm depth can significantly reduce heating costs. Based on Energy Saving Trust figures for 2026, the estimated annual savings on gas bills are:
| Property Type | Estimated Annual Saving |
|---|---|
| Detached house | Around £355 |
| Semi-detached house | Around £215 |
| Mid-terrace house | Around £145 |
At these savings rates, loft insulation typically pays for itself within 1 to 3 years. A better energy performance certificate (EPC) rating can also make a property more attractive to buyers and, increasingly, is considered by mortgage lenders offering green mortgage products.
Types of Loft Insulation
- Blanket rolls — The most common type in UK homes. Made from mineral or glass wool, blanket insulation is laid between joists, with a second layer running across the top. It's widely available, performs well, and is the most accessible option for DIY installation. Costs around £10 per m² for materials.
- Loose-fill — Made from lightweight materials such as cellulose or mineral wool granules, loose-fill is poured between joists. It's well suited to irregular spaces and around pipework, but can shift over time in draughty lofts. Costs around £12 per m² for materials.
- Blown fibre — Similar to loose-fill but machine-applied using specialist equipment. It's effective in hard-to-reach areas and fast to install, but always requires a professional installer.
- Sheet insulation — Rigid boards (typically PIR) cut to size and fitted between or under rafters at roof level. This is used for warm loft installations rather than cold loft floor insulation.
What is the ideal thickness for loft insulation? Does it depend on your home?
"The recommended depth of blanket style insulation (glass or mineral wool) for a loft is 250mm to 270mm."
What's Involved in Installing Loft Insulation?
Before the Job Starts
- Pre-Checks — The installer assesses access, existing insulation depth, ventilation, electrics, and any tanks or pipework that need attention first.
- Preparation — Any damp, leaks, or pest damage must be resolved before new insulation goes down.
During the Job
- Installing the Insulation — Insulation is laid between and over the joists to the specified depth, working carefully around any obstructions.
- Maintaining Ventilation — Clear gaps are left at the eaves to maintain airflow. Downlights are guarded or boxed if needed.
- Raised Loft Legs — If boarding will be added over the insulation, loft legs are installed at this stage to protect the insulation's depth.
After the Job
- Safety Checks — The installer confirms ventilation paths are clear, cables and tanks are accessible, and the insulation isn't compressed anywhere.
- Advice — A reputable installer will flag any pipes or tanks that now need lagging, given the loft will run colder once properly insulated.
Spray Foam Insulation
Spray foam is occasionally used in loft spaces, but it carries significant risks that are worth being aware of before proceeding. Many UK mortgage lenders, including major names such as Halifax, Nationwide, and TSB, will not lend on properties where spray foam has been applied directly to roof timbers, as it prevents surveyors from inspecting the timber for rot or moisture damage.
If you're buying or selling a home with spray foam insulation already in place, removal may be necessary to restore the property's mortgageability. The average cost of spray foam removal is around £40 per m², and most jobs take 1 to 3 days to complete. See our full spray foam removal cost guide for a complete breakdown.
Can I Insulate a Loft Myself?
Laying blanket insulation rolls between loft joists is one of the more manageable DIY jobs in a home, provided the loft has reasonable access and there are no complications. However, lofts can be cramped, poorly lit, and dusty — and working in them carries risks if you're not careful.
Blown and loose-fill insulation require specialist equipment and are better left to professionals. Any job involving electrical cables, downlights, or existing damage should also be handled by a qualified installer.
If you do take on the job yourself, wear protective gear — gloves, goggles, and a dust mask — as glass and mineral wool fibres are skin and respiratory irritants. Always leave a clear ventilation gap at the eaves and never compress the insulation.
DIY Preparation Only
Even if you plan to use a professional installer, you can help reduce costs and save time by preparing the loft in advance:
- Clear any stored items from the loft to give the installer clear access.
- Check for any visible signs of damp, leaks, or damaged timbers and have these resolved first.
- Make sure the loft is accessible with a safe ladder or hatch.
- Arrange temporary lighting if the space is particularly dark.
Building Regulations for Loft Insulation
UK building regulations require loft insulation to be at least 270mm thick for new installations. Installers must leave clear ventilation gaps at the eaves and ensure that electrical cables, downlights, and water tanks are kept safe and accessible. If the loft is to be boarded afterwards, the boards must be raised above the insulation using loft legs to prevent compression and maintain airflow.
Approved Document L sets out the current energy efficiency standards for retrofit work in England. A qualified installer should be familiar with these requirements and able to confirm the work meets them.
Can I Get a Grant for Loft Insulation?
Some households may be eligible for help with insulation costs through government-backed schemes. In 2026, the main funded routes are:
- The Warm Homes Plan — A £13.2 billion government programme designed to deliver energy upgrades to 5 million homes by 2030. Funding is available for households on incomes of £36,000 or less, those in qualifying postcodes, or those in receipt of means-tested benefits. The property must have an EPC rating of D or below.
- Energy Company Obligation (ECO) scheme — Administered by Ofgem, this scheme requires larger energy suppliers to fund energy efficiency improvements for eligible households. The grant typically covers installation only, not additional work such as clearing a loft or fitting boarding.
The simplest way to check eligibility is to contact your energy supplier directly. Grant-funded installations must typically be carried out by a TrustMark-registered or MCS-certified installer.
Removing Old Loft Insulation
Sometimes existing insulation needs to be removed before new material can be installed. This is most common when older insulation has degraded, been damaged by damp or pests, or was fitted incorrectly in the first place.
Most installers will dispose of old insulation as part of the job. As a guide, allow an extra £250 to £400 on top of installation costs to cover removal and disposal. The final figure depends on the size of the loft and the volume of material to be cleared.
If spray foam insulation is present, removal is a specialist job that costs significantly more — around £40 per m² on average.
Checklist: Finding a Loft Insulation Contractor
When comparing contractors, a few simple checks can reduce the risk of problems and give you a clearer idea of value for money.
- Get multiple quotes — Compare at least 3 prices. Be cautious of quotes that seem unusually low, as this can indicate shortcuts or poor-quality work.
- Check experience — Ask about similar projects completed and request to see photos of previous loft insulation jobs.
- Read reviews — Look for consistent positive feedback on their MyJobQuote profile page. Repeated complaints are a warning sign.
- Confirm what's included — Make sure you're clear on exactly what's covered in the quote. Ask whether the price includes disposal of old insulation, pipe lagging, vapour control layers, or any electrical safety checks.
- Check installer credentials — For grant-funded work, installers must be TrustMark-registered or MCS-certified. It's worth verifying this before proceeding.
Ask a Trade
Got a question that only a tradesperson can answer? We have thousands of trades ready to answer any question you may have.
Ask your question
FAQs
How Long Does Loft Insulation Take to Pay for Itself?
Loft insulation usually pays for itself within 1 to 3 years through lower energy bills. After that, the savings continue for as long as the insulation remains effective — typically 40 years or more.
How Long Does Loft Insulation Last?
Loft insulation typically lasts 40 years or more when kept dry and undisturbed. It may need replacing sooner if it's been compressed, damaged by damp, or disturbed by pests.
Can Loft Insulation Cause Damp?
Properly fitted insulation should not cause damp. Installers leave ventilation gaps at the eaves to allow airflow. Problems only arise if insulation is compressed, covers vents, or is installed incorrectly — which is another reason to use a professional installer.
What Is the Minimum Thickness for Loft Insulation in the UK?
UK building regulations recommend a minimum depth of 270mm for mineral wool loft insulation. This gives a U-value of around 0.16 W/m²K, which is the current standard under Approved Document L for retrofit work in England.
Can I Insulate a Loft If I Want to Use It for Storage?
Yes — insulating and boarding a loft are separate jobs but can be done together. If you plan to add boarding over new insulation, loft legs must be used to raise the boards above the insulation so it isn't compressed.
Is It Worth Replacing Old Loft Insulation?
Not always. If existing insulation is dry, undamaged, and simply below the recommended 270mm depth, topping it up is usually cheaper and just as effective as a full replacement. Replacement makes sense where insulation is damp, compressed, damaged by pests, or was incorrectly installed in the first place.
Can I Lay New Insulation Over Old?
Yes, provided the existing insulation is in good condition — dry, uncompressed, and free from damp or pest damage. The new layer is typically laid at a 90-degree angle across the joists on top of the existing material to reach the recommended 270mm total depth. A professional can assess whether your existing insulation is suitable to build on.
Does Loft Insulation Add Value to Your Home?
It can. Insulation improves a home's EPC rating, which can make it more attractive to buyers and is increasingly considered by mortgage lenders offering green mortgage products. It also reduces running costs, which is a practical selling point. Because it's relatively low-cost compared with other home upgrades, the return on investment tends to be strong.
