Gambrel Roof Snow Load

Per horizontal square foot is expected to support nearly 12 inches of wet heavy snow.

Gambrel roof snow load. Or if the building was poorly designed or constructed. 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. Thus a roof designed to carry a snow load of 20 lbs. Length of high roof lu.

The snow load calculations provided by this online tool are for educational and illustrative purposes only. Use of manufactured roof trusses can dramatically cut labor costs when framing a gable roof compared to building rafters. Length of roof downwind of the snow drift. Length of roof upwind of the snow drift.

Length of low roof ll. An inch of water depth weighs 5 2 lbs. Snow load is the downward force on a building s roof by the weight of accumulated snow and ice. Even though the sloped design of a gambrel roof works well for rainfall when it occurs the flatter upper portion of this option tends to accumulate snow in ways that a steeper angle wouldn t collect.

Consult local building codes for snow load capacity and reference the span tables for joists and rafters published by the american wood council awc as a general rule roofs that have a high human occupancy rate should be framed with rafters every 16. Horizontal distance from eave to ridge. Trusses can be constructed with smaller sized lumber than rafters and often their cost is not significantly higher than normal rafters. Figure 7 1 pages 84 85 and table 7 1 page 92.

The water content of snow may range from 3 for very dry snow to 33 for a wet heavy snow to nearly 100 for ice. This roof design offers poor resistance to snow accumulation. Ground snow load pg. That means a heavy snowfall over a long time can result in enough pressure on.

To calculate a gambrel roof select gambrel roof from the roof type dropdown list or click on the appropriate toolbar button to calculate a. This web based application is made freely available courtesy of the advertisements displayed on this page. Medeek design assumes no liability or loss for any designs presented and does not guarantee fitness for use. The determination of the drift load that is.

Besides its unique appearance a gambrel roof also serves to maximize the usable floor space in the attic area. The roof or the entire structure can fail if the snow load exceeds the weight the building was designed to shoulder.