How do I know whether I have solid walls or cavity walls?

Insulating cavity walls is one of the most effective energy saving measures you can carry out in the home, helping to reduce heat loss.

‌You can usually tell by the pattern of brickwork. Cavity walls only became widespread after the 1930s and only after the mid 1980s were homes generally insulated during construction. If you can see brick headers, the ends, apart from around doors and windows, it is a sign of solid walls without a cavity (left pattern on the image). The brickwork pattern on the right usually indicates cavity walls.‌‌

Cavity wall insulation

Around 35% of heat loss can occur directly through walls compared to 10% through windows. Wall insulation saves around £115 a year on heating bills and these savings will increase in future as fuel costs rise.

The most common material used is rock or mineral wool. The material is blown into the cavity. All cavity insulation materials are resistant to water penetration. It won't transmit water across the cavity or absorb it from below the damp course.

Work is guaranteed for 25 years by the Cavity Insulation Guarantee Agency (call 01525 853300 or click here to visit the CIGA website)

DIY solid wall insulation

SEMPATAP thermal solid wall insulation is 10mm thick, specifically developed as solid wall insulation and has been in use in the UK and Europe for over 20 years. It is a remarkable thermal insulation which, when applied inside the property on the external walls, substantially reduces heat loss making rooms immediately feel warmer. It is often referred to as ‘magic wallpaper’, ‘insulated wallpaper’ or ‘flexible insulating lining’.

SEMPATAP is as simple as wallpaper to apply with hardly any mess and can be decorated with virtually any finish - emulsion, wallpaper - it can even be tiled. It can be redecorated and has a life expectancy of 30 years. It can be easily applied on a DIY basis and there is an application DVD available for all homeowners living in hard to heat homes wishing to undertake DIY insulation.

Contact us

Energy and Home Support Team
Newark and Sherwood District Council
Kelham Hall
NG23 5QX

Freephone: 0800 0131689

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    Newark and Sherwood District Council
    Kelham Hall
    NG23 5QX

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