Roof Tributary Load

An outlooker can be defined as a framing member that supports the portion of the roof beyond the face of a gable end truss.

Roof tributary load. 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. Tributary areas for gravity loads. 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. 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.

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. If the load is 100 psf the load to the beam would be 12 ft x 100 psf 1200 plf. 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. 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.

The left wall has 7 ft of tributary width and would receive a load of 700 plf. The area from the center between two beams to the center of the next two beams for the full span is the load on the center beam. It can also be called the load periphery. The tributary load on the member is found by concentrating or.

The tributary area is a loaded area that contributes to the load on the member supporting that area ex. Notice that the middle tributary zone must carry more weight than the adjacent areas b and d. If the load is 100 psf the load to the beam would be 12 ft x 100 psf 1200 plf. E tributary width tributary loading or tributary width is the accumulation of loads that are directed toward a particular structural member.

The tributary area times the pressure on the surface. Tributary width is 7 ft 5 ft 12 ft. This means that one is a fixed node and the other is a rolling node. 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.

The left wall has 7 ft of tributary width and would receive a load of. 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.