Roof Snow Load

Overestimation of snow loads can unnecessarily increase the cost of construction.

Roof snow load.

If your roof is flat it is more likely to have snow load problems than if it is pitched. On multiple factors including. Where snow isn t a problem the live load can come from people working on the roof and any equipment they. The determination of the drift load that is.

In our case let s assume that our structure has a flat roof roof slope 5. The roof or the entire structure can fail if the snow load exceeds the weight the building was designed to shoulder. Other considerations for sloped roofs can be found throughout chapter 7 of asce 7 10. Or if the building was poorly designed or constructed.

Wind exposure of roof. The snow load that is applied to our structure is not the ground snow load but in most cases the flat roof snow load. It is determined based. Importance occupancy and use of the building.

How snow load can damage your buildings. You need to use a snow load formula for flat roofs. Hipped roofs are often used in complex roof formations with the hips facing different directions. These distinctive roofs with overhanging eaves feature four medium pitched sides and are characteristic of dutch architecture and help disperse snow loads in northern climates.

The truss could be designed based on the assumption that the 25 psf roof snow load is a factored ground snow load in which case a ground snow load is back calculated using asce 7 based on the specified roof snow load pg 25 psf therein lies the problem with specifying only a roof snow load. The minimum design roof snow load. Snow load is the downward force on a building s roof by the weight of accumulated snow and ice. The flat roof snow load is calculated using formula 7 3 1.

The easiest way is to push a yardstick into the snow on the roof selecting an area that looks typical of the overall snow depth. Snow loads are influenced by elevation general weather and moisture patterns slope direction exposure roof or trail bridge configuration and wind direction and severity. First figure out how deep the snow is piled up there. In areas of the state outside of certified local government jurisdictions the design snow load shall be based on the ground snow loads developed in snow loads for structural design in montana authored by f f.

Schilke civil agricultural engineering montana state university august 1989. The live load on a roof is the weight of any temporary objects on the roof.