How to insulate cavity walls

If your house was constructed with cavity walls that are not insulated, then adding insulation could keep your home cosier and cut your heating bills. But it’s important to choose a method of insulation that’s right for your property – or you could end up with a damp problem.

In this section, you’ll find an overview of the options for insulating your walls, roof and floor.

Cavity wall insulation

Older cavity-wall properties were generally built without any additional insulation, relying instead on the air gap created by the cavity itself.

If this is the case for your property, and if you feel your home is losing too much heat, you may want to add insulation to your walls.

Options for cavity wall insulation:

  • inside the wall cavity
  • added to the wall, on the inside of the room
  • added to the wall, on the outside of your house

The right option for you will depend on a few different factors, like how much building work you want to do, the size of your rooms, your home’s location and how exposed it is, and your budget.