Solid wall insulation - what is it and how much can I save?   

If your house was constructed before 1940 chances are your walls are made up of solid brickwork. The heat lost through this kind of wall is around 35%. Solid wall insulation is a method available that will slow down the rate at which the warm air inside your house escapes through the walls. You can effectively cut your energy bills by as much as 25% using this method.

Solid wall insulation is basically a compound scheme consisting of three layers - an insulator, a bonding agent and cladding with decorative outer layer. There are two types of solid wall insulations– the external and internal.

External Wall Insulation

The usual way of installing external wall insulation includes fastening insulation boards of typical sizes to the wall and supporting it with a cladding finish. The thickness of the boards are in the range of 40 mm to 90 mm and a bonding agent and mechanical fasteners are used to fix them to the wall. The overall width of the insulation will be between 50-150 mm. It is recommended to include this kind of work when planning to have a home renovation in order to minimize the cost.

Internal Wall Insulation

Internal wall insulation is also known as dry-lining and it consists of attaching a layer of insulation that is around 25 mm to 50 mm thick within the outer walls. It is then finished with plasterboard fastened with a bonding agent and fasteners. The total width is 40 mm to 100 mm.

Costs and Savings

External solid wall insulation. Insulated cladding is priced per m2 from £40 to £60. The factors that will determine the total costs are: installer, insulation materials, complexity and condition of the wall. For a house that has around 80 m2 wall area, the cost ranges from £3,500 to £5,500.

You can save around £85 to £120 annually on your energy bills and the insulation will pay for itself in about 15 years. The life span of the installed insulation will be about 30 years.

Internal solid wall insulation. If you have decided to hire a specialist-installer, the insulation cost for a typical house with 3 bedrooms would be around £650. Otherwise if you want to do it yourself, the cost would be around £450. These costs already include the materials. You can save around £75 to £100 per year on energy bills. If it's been done by a specialist, the payback period is around 6 years and do-it-yourself jobs will be around 3 years.

Grants for energy efficiency

Grants are being offered in the UK to help those who want to improve the energy efficiency of their homes and this includes solid wall insulation. Click here for the Energy saving grants in the UK.

The advantages of having solid wall insulation:

• Cut your fuel bills by as much as 25%
• Enhance the resistance of the walls against fire and moisture
• The insulation can repel noise coming from outside
• Slows down the rate in which heat escape from your house having the warm air stay longer indoors
• Decrease the carbon dioxide production of your home helping reduce pollution

An Energy Performance Certificate can tell you exactly how energy efficient your home is.

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