Why you need to insulate your attic

If your home was built before 1985, it’s highly unlikely it’s adequately insulated. That was the year The Building Act 1984 came into power. It obliged local authorities to enforce building regulations in their areas. Since then, developers have had to build properties that comply with increasingly rigorous insulation standards.

Insulating your attic, for example, will keep your home warmer and save you money. According to the Energy Saving Trust, by installing 270mm of mineral wool insulation, a typical detached English home’s energy bills would fall by £190 per year (the carbon dioxide saving would be 950kg over the same period). A mid-terrace house in a similar location would save £285 (and 500kg).  These figures are hardly surprising; a quarter of a home’s heat is lost through an un-insulated loft.

The Energy Saving Trust estimates the installation costs to be £395 and £295 respectively. But, if you’re a reasonably competent DIYer, you can cut these prices in two. So, the payback time is very short. It’s an even more compelling proposition given that loft insulation has a shelf life of at least 40 years.

There are also grants available which cover the entire cost.  For example, if you or anybody in your home is in receipt of Pension Credit or Child Tax Credit, you are likely to be eligible for 100 per cent funding. For a full list of who is eligible, Google “free loft insulation”.

By insulating, the temperature in your attic will reduce. If your attic isn’t adequately ventilated, that could lead to higher levels of damp. Moreover, during the winter any water pipes in the attic are more likely to freeze. Make sure you insulate the pipework too (and the water tank, if you have one).

Cold drafts from the loft hatch are also more likely. You can insulate the hatch with thin insulation board and seal the gaps with draft-excluding strips.

Typically, you need to use two layers of mineral wool insulation. The first layer should be laid between the ceiling joists. The second should be laid at right angles to the first layer.

If you want to use the attic for storage (which most people will), just put one layer down, so you can put boards onto the joists. You will end up with less effective insulation, but a more useful loft. The other option would be to screw battens onto the ceiling joists to create more depth. This strikes me as a tricky, dirty, hot job—perhaps one to avoid.  Either way, make sure you leave a ventilated air gap beneath the boards (and don’t compact the insulation).

It’s possible to get these insulated by a professional. They will fill the space with loose insulation material (similar to packaging material) by means of blowing it into the cavity. This is not expensive and shouldn’t be too messy.

Insulating your attic is one of the few guaranteed ways to save money. Even if you’re planning on selling or letting your property it makes sense—an Energy Performance Certificate (EPC) is a mandatory requirement in both circumstances. Perhaps, more importantly, it will make your home toasty warm. And, winter is coming.