Solid walls let through twice as much heat as cavity walls do! That is why solid walls insulation can help you reduce significantly your energy bills. Solid walls can insulated from the inside or from the outside of your house.
Your house is likely to have solid walls if it was built before 1920. More recent houses generally have cavity walls. Unlike solid walls, cavity walls are made of two layers with a gap between them. If insulating solid walls is more expensive than insulating cavity walls, the energy savings are greater with solid walls.
How much can I save with solid walls insulation?
These figures are estimated. They are based on installing cavity wall insulation on a semi-detached three bedroom house.
What is the difference between internal wall and external wall insulation?
1. Internal walls insulation:
Can be a rigid insulation board fitted to the wall or a stud wall filled with mineral wool fibre.
- Advantages: cheap to install
- Disadvantage: reduces the floor area of the rooms in which it is applied, is disruptive to the household, makes it hard to fix heavy things to the walls
2. External wall insulation:
Can be a rigid insulation board fitted to the wall or a stud wall filled in with mineral wool fibre.
- Advantages: isn’t disruptive, doesn’t reduce the floor area of the rooms, fills gaps in the brickwork and renew the appearance of the walls, improves sound resistance and waterproofing, reduces condensation on inside walls
- Disadvantages: expensive, may require planning permission, requires good access to the external walls
To keep costs down, the best solution is to fit insulation on your walls when you are running other home improvements either outside the house for external walls insulation or inside for internal walls insulation. If you are planning to fit a new kitchen, paint the walls or change your windows; you may as well take the opportunity to improve the insulation of your interior walls. The same works for external walls insulation if you are changing your roof or fitting solar panels.
Solid walls insulation, comply with the regulations
If you insulate a solid wall, you have to make sure it complies with the current Building Regulations. Your installer will normally arrange that.
How can I finance solid walls insulation?
You can finance solid walls insulation through the new government energy efficient home improvement scheme, the Green Deal (click here to learn more and see if you are eligible) . You pay back this investment through savings on your energy bills. Another subsidy called ECO (click here) might also be available too.