Roof Load Width Explained

Most commonly the roof s internal support structure is composed of a fairly complicated system of structural elements designed to manage the load from the roof.

Roof load width explained.

These diagrams may also be used to determine roof load width for floor joists. Roofs are under a lot of pressure. Trusses struts and props. This information is found in the code book.

2 you must determine the snow load for your region. The dead load on a roof includes the framing sheathing and roofing material along with any other permanent construction that rests directly on the roof and transmits its weight load through the. Spacing should be interpreted as the centre to centre distance between adjacent parallel members. So consider a simple gable roof on a 24 foot wide ranch framed with 2 6 exterior walls and a 1 1 2 ridge.

The north zone design live load equates to 40 pounds per square foot the middle zone equates to 30 pounds per square foot and the south zone equates to 20 pounds per square foot. Roof pitch refers to the amount of rise a roof has compared to the horizontal measurement of the roof called the run. Has the highest load. Any areas between the wall corners that are not included within zone 5.

In order to stay intact and in place a roof must be able to resist loads both permanent and temporary that are pushing. Roof load width rlw and floor load width flw can be determined from as1684 or from the images below. This zone accounts for about 5 of the roof surface represented the corners of the roof. The entire roof load is supported by load bearing walls which in turn transfer weight to the foundations of your home.

Load limits on the roof of a building. The snow load is treated as a live load when you use af pa s tables. The span would be 11 5 3 4. Used for roof overhang area along the perimeter of zone 3.

The north zone middle zone and the south zone are identified on the roof load zone map above.