Roofing Framing Details

The framing of a basic gable roof is based on a right angle triangle and the various roof framing components fit the triangle.

Roofing framing details.

The run or half the building span is the base of the triangle. The roof sheathing consisted of inch thick wide pine boards nailed to the purlins and thick enough to resist much sagging. The rise or height of the roof at its peak is the altitude of the triangle. Roof framing can be simple or complex depending on the roof.

Include roof pitch roof geometry slope length and climatic factors such as heavy snowfall or rainfall. And the line length measurement from the roof peak to the building wall is the hypotenuse. The function of each component is. In a rafter roof all of these components are required to provide a stable roof.

Partially these will depend on the style of roof you ve selected but you ll also have some wiggle room depending on the design elements of the house. Rafters act more like the top chord of a roof truss than as a roof joist. Refer to the details. Overhangs hips and dormers add greatly to the complexity of the framing.

The original roof was built using purlins beams extending between gable ends. Standard stick framing or the newer truss framing. Needed to tie the roof together where the rafters are framed at an angle to each other. The rafters carry the applied loads to the exterior walls.

Stick truss roof framing. Whenever possible begin trim installation at the downwind end of the roof farthest away from the source of prevailing winds to al low flashing laps to face away from wind driven rain.