Home insulation

Insulating your home is one of the easiest ways to reduce your heating bills and carbon footprint. If your loft and walls aren’t well insulated, your home could be losing about 25% of heat through the roof and 35% through cavity walls (based on a 3-bed semi).

Houses built these days will typically have loft insulation that’s at least 270mm thick. If you have 100mm or less, consider getting it topped up. Unless you have a room in the loft, it’s best to lay the insulation on the floor so that the heat from the rest of your home doesn’t seep into the loft and leak out of the house.

To avoid potential damp, make sure there are no gaps in the insulation and that the loft is adequately ventilated. Be aware that, if you use your loft for storage, you may need to relocate your belongings or add boards between joists if these are higher than the height of the insulation – don’t squash the insulation!

Many homes are built with a double layer of brick separated by a gap. Newer homes (from about the mid 1980s onwards) incorporate insulation into the construction itself, whereas older homes often need insulation added.

You might have a Cavity Wall Insulation Guarantee Agency certificate to certify that your home had cavity wall insulation installed, or you might see faint traces of drill holes in the mortar between the brickwork where insulation was blown into the wall. If you don’t have these, and your Energy Performance Certificate suggests your walls are not insulated, ask a professional for advice. There are a small number of properties that aren’t suited to standard insulation materials, either because of narrow cavities or inclement weather conditions.

Southampton was one of the first areas in the country to introduce cavity walls in the late 1800s. Homes built before this time had solid walls, and some newer homes made of concrete also have solid walls. Solid walls are more difficult and expensive to insulate than cavity walls. They can either be insulated from the outside, by attaching insulation boards to the wall and covering them with a render/cladding, or from the inside by adding insulation to internal walls and finishing with plasterboard.

If your home is heritage-listed, you may not be able to get external wall insulation. Internal insulation can be a bit more disruptive since door frames, electrical sockets, skirting boards and other fittings will need to be adjusted, and some of the room space will be lost to the additional insulation. Internal wall insulation, however, allows you to tackle the project room-by-room.

Loft and cavity wall insulation can quickly make your home easier and cheaper to heat in winter and keep cool in summer. For personalised advice, including potential access to grants, please contact us using the options below.