Roof Tributary Load

Tributary width is 7 ft 5 ft 12 ft.

Roof tributary load.

Tributary loading or tributary width is the accumulation of loads that are directed toward a particular structural member. The tributary load on the member is found by concentrating or. This concept typically considers the tributary area that a member must support. If the load is 100 psf the load to the beam would be 12 ft x 100 psf 1200 plf.

Load calculation for each tributary area a 40sqft x 50psf or 2000 lbs b 19 5sqft x 50 psf or 975 lbs c 21 sqft x 50 psf or 1050 lbs d 19 5sqft x 50 psf or 975 lbs. In order for a roof truss load to be stable you need to assign two of your nodes on each truss to be support nodes. Our sample homes are in an area where the snow load is 50 pounds per square foot of roof area treat snow as live load. This means that one is a fixed node and the other is a rolling node.

Tributary areas for gravity loads. E tributary width tributary loading or tributary width is the accumulation of loads that are directed toward a particular structural member. Tributary width is 7 ft 5 ft 12 ft. It goes without saying that in a warmer climate the snow load probably would be less so you need to check your code book for live loads and dead loads in your region.

Loads uniformly distributed over an area of roof or floor are assigned to individual members rafters joists beams girders based on the concept of tributary area. The left wall has 7 ft of tributary width and would receive a load of. The tributary area times the pressure on the surface. It can also be called the load periphery.

11 04 2014 if the beam is supporting a floor roof or wall that has a pressure loading normal to the surface the total force on the beam equals the area of surface supported i e. The left wall has 7 ft of tributary width and would receive a load of 700 plf. It is necessary to remember that gable trusses with outlookers having an overhang of more than 1 ft will be under loaded if designed to support the load generated by a tributary area equal to 2 ft of roof load only. If the load is 100 psf the load to the beam would be 12 ft x 100 psf 1200 plf.

The tributary area is a loaded area that contributes to the load on the member supporting that area ex. An outlooker can be defined as a framing member that supports the portion of the roof beyond the face of a gable end truss. Notice that the middle tributary zone must carry more weight than the adjacent areas b and d.