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Loft insulation

Without loft insulation you could be losing as much as 15% of your heating costs through your roof. Insulating your loft is a simple and effective way to reduce your heating bills and you can even do it yourself.

Watch our video guide to loft insulation.

How loft insulation works

It acts as a blanket, trapping heat rising from the house below. You should also consider lagging your pipes at the same time for optimum efficiency.

The savings

If you currently have no loft insulation and you install the recommended 270mm depth you could save around £155 a year on your heating bills and around1 tonne of carbon dioxide (CO2) per year.

The following table gives approximate costs, savings and paybacks for loft insulation however the typical cost provided does not include any financial support or grants. Financial help may be available if you're planning to make energy saving improvements to your home.

The Government, energy suppliers and local authorities all provide grants or offers to help you implement energy saving measures in your home. For more information or to search for energy saving grants and offers, please click here.

  Loft insulation
(0 - 270mm)
Loft insulation
(50 - 270mm)
Annual saving per year (£) Around £155 Around £45
Installed cost (£) Around £500 Around £500
Installed payback Around 3 years Around 11 years
DIY cost From £250 Around £180
DIY payback From 2 years Around 4 years
CO2 saving per year Around 1 tonne Around 300kg

How the savings add up

If everyone in the UK topped up their loft insulation to 270mm, around £560m would be saved each year. That's enough money to pay the annual fuel bills of around 530,000 families.

How it is installed

Insulation is simply laid over the floor of the loft, between and then over the joists if they are visible. Protective clothing, gloves and masks should be worn. Care must be taken not to insulate below the cold water tank, if one is present, and not to compress the insulation in tight corners or eaves. Walk boards can then be laid over the joists to provide safe access from the loft hatch to any water tanks (if present).

Loft insulation can be carried out as a DIY task or by a professional installer. There are grants and offers available to help you pay for loft insulation.

Find out if you're entitled to a grant or offer

What to do next

If you have other questions why not visit our FAQ section. If you still have other questions why not call your local Energy Saving Trust advice centre on 0800 512 012 for free, impartial advice on saving energy in your home.

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Help and advice

Call 0800 512 012 for free, independent and local energy saving advice

Click here to contact your local advice centre.