GBIS - Loft, Cavity and Internal Wall Insulation

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Loft insulation is one of the most effective ways to boost your home’s energy efficiency. 

It works by laying mineral wool across the loft floor, creating a thermal barrier that helps prevent up to 25% of heat loss through the roof.

About a quarter (25%) of the heat in your home escapes through the roof. Adding insulation creates a thermal barrier that makes it more difficult for this heat to escape, it’s like putting a hat on your house.

By reducing heat loss, your home stays warmer for longer periods. This also means your heating system doesn’t have to work as hard to reach its desired temperature, which cuts down on energy usage and helps save money on your energy bills.

In the UK, the recommended thickness for loft insulation is 270mm. While lofts are often used for storing items you don't need year-round, it's important not to compress the insulation by placing items directly on top of it. This can reduce its effectiveness. Instead, it's advised to install loft legs and boards above the insulation and place items on these surfaces.

By insulating your loft, you could also cut your home’s carbon footprint by as much as 1,000 kg annually, the environmental equivalent of planting around 500 trees.

Cavity wall insulation fills the gap between the inner and outer walls of a building. 

About 33% of the heat in your home escapes through the walls. Having the right type of insulation can significantly reduce your energy bills. Properties could save up to £485 a year on their energy bills by improving insulation.  If your house was built before 2010, it likely does not have insulation in the cavity, but it can be retrofitted if necessary.

Cavity wall insulation is a thermal material installed through the external walls of a property into the cavity, which is the empty space between the external and internal walls. It creates a thermal barrier that captures air within the cavity, reducing heat loss and lowering energy bills.

At ecoedge, we use the Thermabead system, which involves mixing small polystyrene beads with a special adhesive and pumping them into the cavity using specialised equipment. The insulation material is injected through small holes drilled into the outer wall at regular intervals, usually about 1 meter apart. After injecting the insulation, we fill the holes and restore the wall to its original appearance. Houses built after 1930 typically have cavity walls rather than solid walls.

Making your home warmer, more energy-efficient and cheaper to heat.

Internal wall insulation is used to insulate the inside surface of external walls in homes. This method tends to be used in older properties (pre-1920s) which do not have a cavity wall. There are two different types of Internal Wall Insulation that can be installed, which is dependent a range of criteria such as wall condition and space constraints.

Insulated Plasterboard tends to be used for homes with smooth, even walls, the thickness of the insulation can be as little as 30mm and is fixed directly to the wall or using mechanical fixing. 

An alternative option is a stud wall with insulation, where a timber or metal framework is filled with insulation and covered by plasterboard. This does increase the amount of wall space lost (up to 150mm), however it can be easier to integrate electrical cables and plumbing and can be designed to accommodate uneven and damp walls.

 This method is effective when renovating and older home. Unlike external wall insulation, which usually requires treating the entire exterior of the property in one go, internal wall insulation can be installed gradually, one room at a time. This makes it ideal for people living in the property during the work or for those on a tighter budget.

You can choose to insulate the most used or coldest rooms first (like living rooms or bedrooms), then complete the rest of the house when convenient. This approach helps spread out the cost and disruption, and allows you to prioritise comfort in the areas where it matters most.