Flat Roof Framing Details

Sizes of joists needed for flat roof construction.

Flat roof framing details.

So any timber joists that are used need to be strong enough to support this weight. The framing of a basic gable roof is based on a right angle triangle and the various roof framing components fit the triangle. It is not ideal for snow or heavy rain but modern materials and proper drainage have helped. As you may imagine there is a fair amount of weight involved here in terms of boards felt etc.

A flat roof must be strong durable and stable throughout its lifetime. Flat roofs are always built at a slight incline at least 1 8 inch per foot. Of course you don t need to live in a modern house to deal with a flat roof. Yet for historic modern style buildings like this old house s cambridge tv project flat roofs are at the core of the architecture meant to reflect the broad horizontal lines of the natural landscape.

If you build a flat roof try to have it slope in multiple directions to drains or gutters. Flat roofs are hard to replace. It must provide adequate protection against the elements keeping the buildings structure and interior dry. When framing a flat roof you will need to create a slight incline.

But now flat roofs often are constructed with fewer layers because of improved waterproofing technology. The run or half the building span is the base of the triangle. Flat roof types. Although flat roofs are cheaper to build than pitched roofs they have a shorter life span.

And the line length measurement from the roof peak to the building wall is the hypotenuse. Old asbestos roofs are often replaced with flat roofs. A roof is considered to be flat when it is of a slope of 1 5 o to the horizontal. A flat roof has a slope of 1 8 per foot to 2 12.

May 9 2017 explore bernice ohene s board flat roof construction on pinterest. Flat roof construction for residential. See more ideas about flat roof roof roof construction. This will help you create a flat roof framing plan.

The rise or height of the roof at its peak is the altitude of the triangle. A roof is defined in bs 6229 as a flat roof if it has a pitch of 10 degrees or less. Some observers suggest it s harder to replace a flat roof than a traditional pitched shingle roof because of the labor required to remove its layers especially on older flat roofs. Think of a flattened hip roof.

This could mean flat roofs may not raise the same red flags they used to.