Internal Wall Insulation: the Advantages and Disadvantages

If your property has solid external walls, you need to make sure that they’re sufficiently insulated. You can do this by fitting insulation on either the outside or inside of these walls.

Internal wall insulation is a popular option and could help you to make your home more energy-efficient. To help you work out whether internal insulation would benefit your home, we’ve made a list of its advantages and disadvantages.

Internal wall insulation advantages

Versatile

A big advantage to internal wall insulation is that it’s versatile. When you fit it you can choose between two options, which lets you pick the best type for your home.

If you want to keep your walls as thin as possible, you can fit insulation boards. These are usually made of plasterboard backed with foamed plastic, which is 6-10cm thick. Or if you have an uneven wall you can build a stud wall in front of it. This involves building a metal or wooden studwork frame, filling it in with mineral wool fibre and then plastering over the top.

Affordable

Another bonus to internal wall insulation is that it’s affordable. Although it costs more than cavity wall insulation, it’s usually cheaper than external insulation. Plus, according to the Energy Saving Trust it can save you between £100 and £450 on your heating bill every year, so is well worth the investment.

Internal wall insulation disadvantages

Reduces room size

Unfortunately, internal insulation does have some downsides. Fitting it will thicken your walls and reduce the size of your rooms. Insulation boards can increase the thickness of your wall by up to around 10cm and stud walls take up even more space.

Makes fixing things to walls difficult

Another downside to internal insulation is that it can make fixing things to walls difficult. Stud walls are strong enough to hold heaving fittings like kitchen units and wash basins. But if you have insulation boards, your fittings will need to be able to go through them and into the wall behind.

Installation can be disruptive

Another thing that puts people off internal insulation is that installing it can be disruptive. All your wall fittings, like skirting boards, switches and plugs, need to be removed before the insulation is fitted then replaced afterwards. Plus, you won’t be able to use a room while insulation is being fitted to its walls.

So internal wall insulation has a range of advantages and disadvantages. To learn about your other options, see our article on external wall insulation. Or to find an insulation installer in your area, click ‘Start my project’ and complete our online form. We’ll find you up to 4 local professionals.

Price

Approx. £4,000 - £13,000

Including materials and installation

Installation time

Approx. 1 day

To insulate an average room


Advantages and disadvantages
  • Versatile
  • Affordable
  • Reduces room size
  • Makes fixing things to walls difficult
  • Installation can be disruptive