Flat Roof Extension Building Regs

To comply with part l of the building regulations flat roofs must achieve u values of 0 18 w m k or lower.

Flat roof extension building regs. When installing or repairing a flat roof you must adhere to building regulations. This is placed over the roof joists and an board normally external ply is laid on top. To enable compliance with the requirements of the building regulations to be demonstrated full details of the new roof will be needed including materials and their dimensions and performance properties. It must provide adequate protection against the elements keeping the buildings structure and interior dry.

As you may imagine there is a fair amount of weight involved here in terms of boards felt etc. Moreover the costs of a flat roof extension today are typically lower than for a pitched roof. U value of a flat roof. Take inspiration from the ideas above to create an aesthetically pleasing extension for your unique home.

Flat roof types. Warm deck the type of insulation for this is usually of a rigid type and the thickness will vary depending on the manufacturer s specifications. A roof is defined in bs 6229 as a flat roof if it has a pitch of 10 degrees or less. There must be a slope of 1 80.

Insulating flat roof extensions. So any timber joists that are used need to be strong enough to support this weight. This usually consists of felting which has a slight fall to allow rain water to drain off to enable compliance with the requirements of the building regulations to be demonstrated full details of the new roof will be needed including materials and their dimensions and performance properties. Part h of the building regulations regarding drainage state that water should drain to one or two edges.

Traditionally flat roofs were constructed with cold decks where the spaces between the joists were packed with mineral wool type insulation placed above the ceiling like a. Flat roof this usually consists of felting which has a slight fall to allow rain water to drain off. The flat roof extension is more on trend than it once was and is free of the dreaded leaks that haunted this type of structure in the past. Ventilation is required for these roofs.

A lower u value indicates better insulation properties hence u value requirements usually specify a maximum value. Old asbestos roofs are often replaced with flat roofs. Sizes of joists needed for flat roof construction.