Overhang Flat Roof Framing Details

If you are not able to use an angled soffit use one of the two flat soffit details illustrated below.

Overhang flat roof framing details.

Details for conventional wood frame construction the first approach to achieving a strong durable struc ture involving economical use of materials is to follow a. Using a cantilever means you don t need external bracing. Cantilevered structures are popular for homes with balconies. The main component of any eaves detail is the rafter tail the part of the rafter that extends beyond the exterior wall.

There is no reason to use a pork chop eave. It is for that reason that the flat roof construction manual focuses on the subject of designing energy saving flat roofs free from damage. If you must use a flat soffit stop the flat portion of the soffit at the wall to align with the corner board. An overhang protects the upper portion of the wall that it is attached to from rainfall and it also shades the windows under it from the sun.

The rise or height of the roof at its peak is the altitude of the triangle. For gabled roofs the roof rafters extending beyond the wall caps creating an angled roof overhang on the eaves. A cantilever is a rigid structural element anchored only at one end to a vertical support from which it is protruding. The run or half the building span is the base of the triangle.

And the line length measurement from the roof peak to the building wall is the hypotenuse. To determine exactly what the rafter tail will look like i always make a full size drawing on a scrap of plywood of all the eaves elements including framing and finish materials see illustration above. With composite siding such as boral s truexterior siding over a ventilated rain screen and with properly executed flashing at the windows and doors the walls on the fhb house will be able to handle rain just fine. Roof overhangs at the eaves and rakes protect the walls below from rain and sun.

Flat soffit stopping at end wall. With a flat shed roof the roof simply extends past the wall plate to provide an overhang. Overhangs are extensions of the roof beyond the exterior wall i e the joists rafters or trusses and the decking they support cantilever past the wall. This is a detail to avoid at all costs.

The framing of a basic gable roof is based on a right angle triangle and the various roof framing components fit the triangle. But are they really necessary. Of course you don t need to live in a modern house to deal with a flat roof. It dealt in detail with flat roof constructions and.

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.