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First published: 21 February 2024 -

Last updated: 14 January 2026 -

Verified by our Editorial Panel

Insulating your home

Insulation is one of the best things we can do to save on energy bills and reduce emissions.  

According to the Energy Saving Trust, the heat lost from a typical uninsulated home:

Through the roof

is

25%

Through the walls

is

33%

Through the floor

is

10-20%

Home Insulation

Insulating your loft, walls, floor, windows and pipes can help stop heat loss in the winter which could save you money on your energy bills. Insulation can also help keep your home cooler in the summer.

Some types of insulation can be installed yourself, and there are government schemes and green finance options that can help cover the costs. Depending on the kind of property you live in, and your budget here are some options to consider:

DIY

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Draught-proofing

Draught-proofing strips are a useful and inexpensive way to seal unwated gaps. They sit beneath windows and doors to help stop cold air from coming in, and warm air from escaping.

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Add insulation film to windows 

Insulation film is easy to fit and keeps heat in when it’s cold outside, and reduces heat from the sun in the summer time. You could go a step further and add thermal-lined curtains to keep rooms even cosier in the winter. 

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Hot water insulation 

Insulating pipes, tanks and radiators can be a quick, easy and affordable way to save money on energy bills. Adding a jacket to your hot water cylinder if you have one also helps keep your water hotter for longer.

Professional installation

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Window double glazing 

Double glazing helps keep your home warm in winter and cool in summer, making it energy-efficient all year round.

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Wall insulation 

Get professional advice first, as the wrong type of insulation can make it more difficult to keep a home cool and make condensation worse.

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Roof insulation 

Insulating the loft or roof is a simple and effective way to reduce heat lot and energy bills.

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Floor insulation 

Seal the gaps between uncarpeted floor and skirting boards using caulk sealant, and add floorboard gap filler to reduce draughts. Just be sure not to block underfloor vents and grilles, as this could lead to moisture build up.

Find out more about the options above on the Energy Saving Trust website. You can also find out more in the UK Government’s buying green heating and insulation products consumer guide.  

For any major work, find a trusted installer in your area through TrustMark or Which? Trusted Traders.

Financial support

Check our financial support page to find out if you could be eligible for free home energy improvements or other sources of support.

Which? Home Energy Planning Service can also build a free personalised plan for your home to improve energy efficiency, provide estimated costs and ways to reduce your energy bills.

Optimised retrofit scheme

Jayne Martin from Pontardawe had external wall and roof insulation installed in her home as part of the Optimised Retrofit Programme. Find out how it helped her to feel more comfortable and save money.

Find out more

For further support or advice call

0300 0604400

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