Roof and loft insulation

Roof and loft insulation

Insulating your loft, attic or flat roof is a simple way to reduce heating bills and stopping heat escaping upwards.

Why insulate?

Around 25% of heat lost in un-insulated homes is lost through the roof. Loft insulation is a relatively low-cost option, is effective for around 40 years and will pay for itself several times over during this period. Loft insulation can also save you between £45 and £150* on your heating bill every year. It will also reduce your carbon emissions and keep heat out of your house in the summer months. Installation is usually quick and easy, taking between one and two hours hours.

Is my home suitable?

Your home will be suitable as long as it has a loft space which is not boarded, although the type of roof you have may affect your options. You will need to be careful if you intend to lay boards over the joists once the recommended levels of insulation have been installed. Compressing the insulation will make it less effective, although there are simple ways around this. 

How much could I save?

Loft insulation could cut your heating costs by up to 25%. The monetary and carbon dioxide savings may vary depending on a number of factors including how much insulation you already have, your preferred household temperature during the winter, which fuel you use and how long you have your heating on for. The saving could be around £175 per year.

The Energy Saving Trust has estimated the following figures based on wholly insulating a gas-centrally heated, three-bedroom semi-detached home: 

Even if your loft is already insulated, a home energy assessor should check whether you have the recommended insulation depth in order to maximise savings.

Insulation options

The options available for loft insulation vary depending on your home. There are more options available for pitched (sloping) roofs than flat or dormer roofs. An assessor should look at every option during the home energy assessment and make the most suitable recommendations for your property.


Installers will generally complete the entire process in one visit including, where necessary, ensuring appropriate ventilation to prevent a build up of condensation, insulating the loft hatch and protecting the pipes to prevent them from freezing. The entire installation process will generally take no more than half a day. The loft space must be cleared before work can begin.

*source: The Energy Savings Trust