Blog>Cost Guides>Loft insulation costs in 2025

Last updated: 14 March 2025

Loft insulation costs in 2025

Installing loft insulation is a great way to lower your energy bills, keep your home warm, and reduce your carbon footprint. But how much does loft insulation cost? In this post, we cover everything you need to know to help price up your project.

Loft insulation costs in 2025

Fast Facts

  • Quilt insulation (270mm) for a detached house costs around £1,206

  • Labour costs for roof insulation average around £250 per day

  • Most loft insulations can take less than a day to install

  • Insulating your loft improves your home's energy efficiency and heat retention, helping to save money on your bills.

Is loft insulation worth it? How much can loft insulation save on energy bills? We know there's much to consider against the cost of loft insulation, so we're here to help you make sense of it all.

In this post, you'll find loft insulation costs per m² and by property type, making it easy to tot up the average cost of insulation for your home.

We also share the latest information on loft insulation grants, so if you're looking for free loft insulation in the UK, we can point you in the right direction.

How much does loft insulation cost in the UK?

Cost provided itemUnitAverage UK cost (+VAT)
Insulating loft with basic quilt insulationEa£725
Quilt insulation (270mm) (Detached house)Ea£1,206
Quilt insulation (270mm) (Semi-detached house)Ea£825
Quilt insulation (270mm) (Terraced house)Ea£654
Quilt insulation (270mm) (Bungalow)Ea£1,206
Quilt insulation (2 x layers) (materials only)Per m²£10
Loose-fill insulation (material only)Per m²£12
Sheet insulation (PIR) (materials only)Per m²£35
Spray foam insulation (materials only)Per m²£37
Thermal foil layer (materials only)Per m²£14
Labour costPer day£250
Insulation to pipework (materials and labour)Per metre£6 - £35
Upgrading water cistern insulation (materials and labour)Ea£150
Relocating electrical wires (labour)Per day£300
Loft boarding (materials and labour)Per m²£55
Last updated: March 2025
Our costs are ballpark averages - get a local tradesperson to quote now

Average loft insulation costs by property type

It goes without saying, the bigger your loft space, the higher the cost of loft insulation. On average, 270mm of quilt insulation will cost:

  • Detached house: £1,206

  • Bungalow: £1,206

  • Semi-detached: £825

  • Terraced house: £654

See the tradespeople we've checked and recommend for your job

Loft insulation cost per m²

One of the best types of loft insulation for UK homes is quilt (or blanket) insulation. It's affordable and easy to install, but what do the different loft insulation materials cost?

In this section, you'll find the average cost of the four main types of loft insulation:

1. Quilt insulation

Quilt insulation, also known as blanket insulation, is the most common type found in UK homes.

It's typically made from mineral or glass wool and comes in rolls, which are easy to install.

It's great between joists, provides good thermal performance, and is generally quite affordable at around £10 per m².

2. Loose-fill insulation

Loose-fill insulation is good for topping up existing insulation and filling hard-to-reach spaces.

It's often made from eco-friendly, recycled materials, such as cellulose or fibreglass, making it a more sustainable choice.

This type of loft insulation costs around £12 per m².

3. Sheet insulation

Sheet (or board) insulation is best for insulating the underside of your roof.

These rigid boards are typically made of polyisocyanurate (PIR) plastic, and often have fire-resistant properties, making them popular for extensions and conversions.

PIR boards offer high insulation performance at a reduced thickness while being robust and moisture-resistant. For these reasons, expect to pay in the region of £35 per m².

4. Spray foam insulation

Spray foam insulation is sometimes used in irregular or hard-to-reach places.

This expanding polyurethane foam has been used since the '70s, creating an airtight seal that can increase the structural integrity of your roof space.

However, failure to install spray foam insulation correctly can lead to ventilation issues and damp. This is why it can be tricky to get a mortgage on a house with spray foam installation.

For this reason, professional installation is always recommended. Spray foam insulation costs around £37 per m².

Loft insulation: All you need to know

Loft insulation: All you need to know

Thinking of enhancing your home's energy efficiency with loft insulation? Get started with our complete loft insulation guide.

Learn more

Labour cost for loft insulation

Professional loft insulation services tend to sit around £250 per day.

The time it takes to insulate a loft depends on several factors, including the size of the loft and the method of insulation.

For example, quilt insulation takes far less time to install than sheet insulation. Although the day rate is the same, installing sheet insulation often takes twice as long.

Overall, most insulation installations take less than a day. However, this doesn’t account for any additional tasks that might be required.

Additional roof and attic insulation costs to consider

Roof or attic insulation is the same as loft insulation. It's just the different terminology people use. When calculating roof insulation costs, you may need to budget for:

  • Pipe lagging (insulation fitted around water pipes): £6 - £35 per m² (materials and labour)

  • Upgrading water cistern insulation: £150 (materials and labour)

  • Relocating electrical wires: £300 per day (labour only)

  • Installing loft boarding: £55 per m² (materials and labour)

  • Installing a loft hatch and wooden ladder: £170 - £290

Checkatrade tick

On Checkatrade, you'll only find trades who meet our high standards and pass up to 12 checks.

Factors that affect loft insulation costs

We've covered the average cost of the different types of loft insulation, labour costs, and potential extra costs to budget for. However, these should be used as a guide.

Aside from the type and amount of insulation needed, there are several factors that can affect UK loft insulation prices, including:

  • Whether any old insulation needs to be removed

  • The accessibility of the space (limited access may cost more due to the complexity of the installation)

Get a quote for your loft insulation project

For an accurate quote for the cost of your loft insulation project, contact an approved installer with Checkatrade.

Simply enter your postcode, below, to find experienced and reliable specialists in your area.

See the tradespeople we've checked and recommend for your job

Energy savings with loft insulation

One of the key benefits of insulating a loft is the energy savings you'll see on your household bills. The return on investment is impressive too, as our Checkatrade member and insulation expert Matthew Stott from MES Energy explains:

"Due to the increased cost of energy, the return on investment for an insulation measure is up to 230% quicker now than it was pre-price increases in February 2022, when costs spiked at the highest we have ever known."

According to the Government's Department of Energy and Climate Change (DECC), making energy-saving improvements to your home increases its value by 14% on average.

So, we believe investing in loft insulation really is a win-win.

Can I get free loft insulation?

You may be able to get free, or more affordable insulation options through a government grant for loft insulation.

Government grants for loft insulation (UK)

The current schemes that offer free or cheaper insulation to reduce your home’s energy bills include:

Through these schemes, you may also be able to get support to install:

  • Cavity wall insulation

  • Solid wall insulation (internal or external)

  • Flat or pitched roof insulation

  • Underfloor insulation

  • Solid floor insulation

  • Park home insulation

  • Room-in-roof insulation

How to apply for a loft insulation grant

Check your eligibility for support on the government website.

Alternatively, learn more about the current green grants available and costs in our guide.

Find approved loft insulation installers near you

Where possible, always use an approved loft insulation installer.

Find insulation installers registered with recognised organisations, such as the National Insulation Association, on Checkatrade.

See the tradespeople we've checked and recommend for your job

FAQs

How much does it cost to insulate a loft in the UK?

Insulating a loft in the UK ranges from around £654for a terraced property up to around £1,206for a detached house.

Average loft insulation costs range from £10 per m² for quilt insulation up to around £37 per m² for spray foam insulation. Labour costs should be factored in too, at around £250 per day.

What are the benefits of insulating your loft or attic?

Insulating your loft or attic has many benefits, including energy efficiency, heat retention, and potential savings in your bills.

For more information on the benefits of insulating your loft, check out our guide which has all the information you need.

Is loft insulation worth the cost?

Loft insulation is generally considered worth the investment due to its long-term energy savings. It reduces heat loss, therefore less energy is needed to keep your home warm, which lowers your energy bills.

What's the cheapest type of loft insulation?

Quilt insulation is the most affordable type of loft insulation at around £10 per . It offers good thermal performance at a lower cost than options such as PIR boards or spray foam insulation.

How thick should loft insulation be in the UK?

UK building regulations recommend loft insulation to be 270mm thick. However, some installations go for 300mm for additional energy savings.

Should I remove old loft insulation?

It's not always necessary to remove old insulation unless it's damaged, ineffective, or contains a dangerous material such as asbestos. Simply topping up existing insulation can often be a more cost-effective way to improve thermal performance. A professional installer will be able to assess the condition of your current insulation.

Is it worth putting more insulation in a loft?

If your home has less loft insulation than the recommended thickness, it can be worth adding more. However, it's not necessarily the case that 'more' is better - it's best to meet but not significantly exceed the recommended thickness.

Can I get a grant for loft insulation in the UK?

Yes, various grants and schemes are available in the UK to help with loft insulation costs, especially for lower-income households. The Great British Insulation Scheme, The Warm Home Local Grant and the ECO4 Scheme may cover all or part of the cost for eligible households.

How long does loft insulation last?

Properly installed loft insulation can last around 40 years, provided it remains in good condition. Moisture build-up or pests can reduce its lifespan - so regular checks are recommended.

What type of loft insulation is best for my home?

This depends on your loft layout, budget, and needs. Quilt insulation is versatile, easy to install, and cost-effective. PIR boards offer high performance in tight spaces, and spray foam is suited to irregular spaces, but both these options are more expensive.

Does loft insulation cause condensation?

Properly installed loft insulation should not cause condensation. This tends to happen if ventilation is inadequate. A professional installer will ensure sufficient airflow to avoid moisture build-up.

What happens if I don't insulate my loft?

Without loft insulation, your home will lose heat more quickly, which means you'll be paying higher energy bills trying to maintain a warm home. Plus, your carbon footprint will likely increase and you might notice more draughts.

For extensions or heating system replacements, building inspectors will often ask for the existing attic insulation specifications. If they don’t meet the recommended requirements, an upgrade will be necessary before work can be carried out.

Can you install loft insulation yourself?

Although it is possible to install some loft insulation yourself, e.g., blanket or roll, the results are less likely to last. This means you’ll miss out on the cost-saving benefits that led you to install insulation in the first place.

Hiring a professional tradesperson is beneficial for several reasons. Firstly, they’ll dispose of any excess materials for you. Secondly, they’ll prepare the area and ensure the insulation meets the required standards. Lastly, a professional knows what to look for, what equipment to use, and how to protect themselves.

See the tradespeople we've checked and recommend for your job

See the tradespeople we've checked and recommend for your job