Warm Roof Insulation Requirements

How to insulate a roof.

Warm roof insulation requirements.

Column a is for extensions where the existing dwelling s walls and roof u values are worse than 0 70 w m k in the walls and worse than 0 25 w m k in the ceiling. The limiting u value the maximise u value which cannot be exceeded required under current building regulations for the roof is 0 20w m. Building regulations and standards set the levels of thermal insulation required when carrying out building work either for new build or refurbishment projects. Warm deck this is where the insulation is placed on top of the rafters joists and the roof covering is then placed over the insulation.

No ventilation is required for these types of roofs. Warm loft insulation is used on pitched roofs where you are using the loft space as a room or for storage. Browse product options or contact your local insulfoam rep to help you quickly pick the best products to simplify your building envelope needs and fit your project budget all with one supplier. New roofs thermal resistance insulation there are two ways to insulate a roof.

Iecc 2015 requirements by climate zone 3. This means the impervious roofing felt with a high moisture resistance is replaced with a more permeable membrane or a breathable membrane. There must be a slope of 1 80 part h of the building regulations regarding drainage state that water should drain to one or two edges waterproofing should extend up the adjacent walls at least. The principle applied here is warm moist air rising from below is allowed to permeate through the roof membrane removing the need to fully ventilate the roof.

The insulation is installed under the roof in the slope. A warm roof has the insulation above the structural deck which is thus kept warm. This not a code requirement but ought to be only 1 inch is typically specified. Building regulations for insulating a roof heat rises and therefore the building regulations requirements for heat loss through roofs are more stringent than those for walls.

A qualified roofing contractor will be able to advise on this but here are some of the main guidelines. The waterproof layer is above the insulation and a vapour control layer is placed below the insulation. You should leave the space under the roof tiles free from insulation to give adequate ventilation so that you don t get condensation or water coming through the tiles.