Loft Insulation: the Best Way to Keep Your Home Cosy

If you want to keep your home cosy and your energy bills down, you need to make sure you have adequate loft insulation. According to the Energy Saving Trust, a quarter of heat is lost through the roof in an uninsulated home.

You can work out how to insulate your loft by how you want to use it. Keep reading to find out about different types of loft insulation and when you should fit them.

Cold loft insulation

A cold loft is when you fit insulation under your loft floor. This is designed to keep your home heat in your living space below and out of your loft. Creating a cold loft is ideal if you don’t want to use your loft as living space, as it means you won’t waste money heating it.

Using blanket loft insulation, usually glass or mineral wool, tends to be the best way to insulate your loft floor. This fits between and over the top of the horizontal joists that support your loft floor. The recommended depth for this type of insulation is 250-270mm. This is the best option if you don’t need to access your loft or use it for storage.

You can still use blanket loft insulation if you want to store things in your loft but you’ll need to raise the floor. This is to give your insulation enough space and air to work effectively. You can do this by either fitting timber battens across the joists or putting plastic legs on top of the joists to support the new floor.

If you have a cold loft, it’s also important to remember to insulate any pipes in your loft to stop them freezing and bursting in cold weather. You should also make sure you avoid fitting insulation around light fittings and electrical wires.

Warm loft insulation

A warm loft is also known as a hot loft or warm roof. This is when you insulate your roof instead of your loft floor. This keeps your loft and the rest of your home warm and stops the heat from leaking out of your roof.

Roofs tend to be insulated using insulation boards and insulated plasterboard. The insulation boards fit between the roof rafters and then the plasterboard goes over the top. This helps to stop heat escaping and keep your loft warm.

So you can work out where to insulate your loft by thinking about how you want to use it. To find a professional to help you source and fit your insulation, click ‘Start my project’ and complete our online form. We’ll connect you with up to 4 local insulating companies.

Loft insulation cost

Approx. £250 - £400

Including materials and installation

Installation time

Approx. 2 hours - 1 day

Depending on loft size


Advantages and disadvantages
  • Reduces heat loss
  • Keeps your home a comfortable temperature
  • Lowers your energy bills