To ensure that an acceptable minimum level of fabric insulation has been achieved, the average U-values of individual fabric elements should not exceed those set out in the table below.
Maximum average elemental U-values (Elemental Heat Loss Method):
|Fabric Elements || New Buildings & Extensions to Existing Buildings (W/m2K) || Material Alterations to, or Material Changes of Use of, Existing Buildings (W/m2K) |
|Pitched roof, insulation horizontal at ceiling level|| 0.16 ||0.35 |
|Pitched roof, insulation on slope || 0.20 || 0.35 |
|Flat roof|| 0.22 || 0.35 |
|Walls || 0.27 || 0.60 |
|Ground Floors || 0.25 || - |
|Other Exposed Floors|| 0.25|| 0.60 |
If you are looking for a place to start improving your homes energy efficiency, attic insulation is number one. This is one of the easiest and quickest areas to make a difference in your energy costs as 25% to 30% of heat escapes through the roof and the attic is generally an easily accessible area. The energy savings would be approximately 25% over the life of your home and the insulation would have paid for itself in two to three years. The type of attic insulation required depends on a number of factors including, whether it is a new home or an existing home, is the loft a usable space, the depth of the rafters etc. These factors are then taken into consideration in our recommendation for the most appropriate insulation required.