Flat Roof Framing Details

Although flat roofs are cheaper to build than pitched roofs they have a shorter life span.

Flat roof framing details.

Of course you don t need to live in a modern house to deal with a flat roof. Flat roofs aren t architecturally logical as rain and snow will shed much more quickly off a sloped roof. A flat roof has a slope of 1 8 per foot to 2 12. The run or half the building span is the base of the triangle.

Sizes of joists needed for flat roof construction. A roof is considered to be flat when it is of a slope of 1 5 o to the horizontal. But now flat roofs often are constructed with fewer layers because of improved waterproofing technology. The framing of a basic gable roof is based on a right angle triangle and the various roof framing components fit the triangle.

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. Some roofs actually slope in several directions ensuring optimal water runoff. Flat roof types. And the line length measurement from the roof peak to the building wall is the hypotenuse.

It must provide adequate protection against the elements keeping the buildings structure and interior dry. So any timber joists that are used need to be strong enough to support this weight. Flat roofs are always built at a slight incline at least 1 8 inch per foot. Old asbestos roofs are often replaced with flat roofs.

When framing a flat roof you will need to create a slight incline. A flat roof must be strong durable and stable throughout its lifetime. You can do this with a foam layer that exactly fits your roof. The rise or height of the roof at its peak is the altitude of the triangle.

May 9 2017 explore bernice ohene s board flat roof construction on pinterest. As you may imagine there is a fair amount of weight involved here in terms of boards felt etc. This could mean flat roofs may not raise the same red flags they used to. This will help you create a flat roof framing plan.

It is not ideal for snow or heavy rain but modern materials and proper drainage have helped. See more ideas about flat roof roof roof construction. If you build a flat roof try to have it slope in multiple directions to drains or gutters. Flat roof construction for residential.

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.