Roof Load Width Meaning

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 meaning.

However if the attic is intended for storage the attic live load or some portion should also be considered for the design of. Roofs are under a lot of pressure. The roof load width is half of the rafter span. If the load is 100 psf the load to the beam would be 12 ft x 100 psf 1200 plf.

This downward imposed load on the home is also known as the snow load. So each lineal foot of wall must carry the loads imposed by a 1 foot wide strip in that 14 ft region. The north zone middle zone and the south zone are identified on the roof load zone map above. You would require three post to cover the 6 5 mtrs of beam length.

The left wall has 7 ft of tributary width and would receive a load of 700 plf. This video looks at roof load width rlw. Load limits on the roof of a building. If you like this video please subscribe to my channel.

The distance in this case is 12 ft 2 ft 14 ft. These diagrams may also be used to determine roof load width for floor joists. Tributary width is 7 ft 5 ft 12 ft. Tributary loading or tributary width is the accumulation of loads that are directed toward a particular structural member.

If you can source a beam of 6 5 mtrs long in one piece the size required would be 240 by 45 in f5 or f7 or mgp 10. 2attic loads may be included in the floor live load but a 10 psf attic load is typically used only to size ceiling joists adequately for access purposes. Spacing should be interpreted as the centre to centre distance between adjacent parallel members. The exterior wall and the headers within will carry all loads from the mid point of the house between the supporting walls to the outside of the house including the roof overhang.

Rlw is used to calculate the sectional size of some roof members and supporting wall members. A built up roof for example will typically include the built up membrane itself with or without gravel as well as some kind of insulation and cover board which will vary in thickness from roof to roof. If you have single span rafters of 4 8 mtrs the roof load width is 2 4 mtrs.