Cold Flat Roof Design Detail

Optimum roof assembly design to enclose pool.

Cold flat roof design detail.

Flat roof details and information relating to insulating a flat roof. Hopefully this video will help explain the difference between cold flat roof construction and warm flat roof construction this videos show detailed drawings. In a cold weather such roofs are inherently prone to condensation which can cause material decay and deterioration. A roof is defined in bs 6229 as a flat roof if it has a pitch of 10 degrees or less.

A flat roof must be strong durable and stable throughout its lifetime. Cold roof designing buildings wiki share your construction industry knowledge. The building regulations in the uk provide guidance on roof design. Flat roof design guide.

In the case of cold roofs the residential flat roofs have the waterproof placed directly on the deck and any insulation would be placed above the ceiling. Compact unvented roof assembly r value increased to r 50 in very cold climate zones to control ice damming. Flat roof types. Details both in 2d and 3d to give a clear understanding.

Cold roof construction requires that a suitable ventilated air space exists above the insulation layer within which the air is constantly mobile being replenished by fresh incoming air whilst the air resident within the void space is being expelled via a natural vent action at another point. A cold roof system sees the insulation placed immediately above the ceiling between the joists with ventilation space above the insulation. The major difference between the warm flat roof and the cold flat roof has to do with the air flow between the roofing timbers known as joists that help to hold up the roof. In cold climate zones the minimum total r value for the entire unvented roof assembly should be r 40.

There are three recognised designs of flat roof construction. There are design differences for each type. It must provide adequate protection against the elements keeping the buildings structure and interior dry. In very cold climate zones this minimum r value should be increased to r 50.

Installing a warm roof can be extremely straight forward and simple to do. A cold roof is roof in which the thermal insulation layer is located between the ceiling joists meaning that everything above the insulation such as the rafters and any roof space will be colder than the living space below it. This arrangement allows the deck to become cold. When we talk about a warm roof vs a cold roof what we re really talking about is the insulation of the flat roof.

Basically there are two options to choose from when insulating a flat roof.