Flat Roof Framing Plan Details

Flat roofs are always built at a slight incline at least 1 8 inch per foot.

Flat roof framing plan details.

Think of a flattened hip roof. And the line length measurement from the roof peak to the building wall is the hypotenuse. 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. Materials such as the roofing material vents and their location.

So any timber joists that are used need to be strong enough to support this weight. Flat roofs are hard to replace. The rise or height of the roof at its peak is the altitude of the triangle. The plan that is drawn of the roof area may be either a roof plan or a roof framing plan for some types of roofs a roof drainage plan may also be drawn.

If you build a flat roof try to have it slope in multiple directions to drains or gutters. It is not ideal for snow or heavy rain but modern materials and proper drainage have helped. Some roofs actually slope in several directions ensuring optimal water runoff. As you may imagine there is a fair amount of weight involved here in terms of boards felt etc.

You can do this with a foam layer that exactly fits your roof. Although flat roofs are cheaper to build than pitched roofs they have a shorter life span. Sizes of joists needed for flat roof construction. Old asbestos roofs are often replaced with flat roofs.

But now flat roofs often are constructed with fewer layers because of improved waterproofing technology. 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. When framing a flat roof you will need to create a slight incline.

The run or half the building span is the base of the triangle. This will help you create a flat roof framing plan. The framing of a basic gable roof is based on a right angle triangle and the various roof framing components fit the triangle. Roof framing and drainage plans will be discussed in chapter 30.