Insulating your loft will result in significant energy savings, and therefore you can expect to reduce your energy costs dramatically as a result. A huge amount of heat leaks out of your roof if the loft is not insulated, around 30% of heat that you have already paid for.
Loft Insulation is relatively easy to do. If your loft is not already insulated, the cost should be about £275 for the insulation material. Once installed however, you'll save approximately £200 per year in reduced heating costs. Therefore, only 18 months later, the cost of the project has paid for itself in lower energy bills, and every year after that, you'll be saving a significant amount of money on heating costs.
It is recommended that the minimum thickness of Loft Insulation should be 200mm. Mineral Fibre or Fibreglass matting comes in rolls of either 100mm or 200mm thick, the thinner 100mm version being used to lay over existing, older, and therefore usually thinner insulation. This type of insulation is most often used by homeowners confident enough to undertake the work themselves. However, great care should be cavity insulation , and the issue of whether to install yourself or hire a qualified fitter is discussed below. An alternative is loose-fill loft insulation, which is used where the spacing between joists is irregular, or in places where it is difficult to reach to install roll-based insulation.
In both cases, the job of installation may not be quite as easy as first thought. The depth between joists is often lower than the recommended depth of insulation, and some initial preparatory work will therefore have to be completed. This is often achieved by raising the height of the joists with additional timber to the required depth. It's quite a precarious position up there in the loft, and very easy to overbalance. Joists are very narrow to walk on, in fact, you shouldn't attempt to walk on a single joist at all, but instead cover the area in boards resting on the joists on all four sides, to distribute your weight more evenly. Of course, ladders can be quite dangerous, particularly in the often small and dimly-lit conditions of a loft.
There are also hazards in laying the insulation itself, For instance, Mineral Wool insulation can irritate your eyes and throat, and protective clothing should be worn at all times to avoid contact with the skin.