If you have any questions or concerns about specific ground snow loads within the state of washington please call us at 1 425 741 5555.
Roof load requirement grand coulee wa.
On a roof with a slope greater than 4 to 12 the live load limit is typically adjusted downward from 20 psf to 15 psf to allow for the relatively greater dead load on the steeper roof.
Where uniform roof live loads are reduced to less than 20 psf 0 96 kn m 2 in accordance with section 1607 13 2 1 and are applied to the design of structural members arranged so as to create continuity the reduced roof live load shall be applied to adjacent spans or to alternate spans whichever produces the most unfavorable load effect see section 1607 13 2 for reductions in minimum roof.
Purpose of this web site.
Design criteria 2015 codes revised 8 11 2016 grant county building department general information p.
This downward imposed load on the home is also known as the snow load.
For roof snow loads greater than or equal to 100 psf the seismic gravity load w shall include.
The north zone middle zone and the south zone are identified on the roof load zone map above.
Sheikh taheri published by the ui department of civil engineering 1986.
Box 37 ephrata wa 98823 509 754 2011 ext.
All roofs must be designed to sustain loads as follows.
For roof snow loads between 30 and 100 psf the seismic gravity load w shall include not less than 25 of the roof snow load.
The north zone design live load equates to 40 pounds per square foot the middle zone equates to 30 pounds per square foot and the south zone equates to 20 pounds per square foot.
However if the attic is intended for storage the attic live load or some portion should also be considered for the design of.
Use our roof snow load calculator to determine your design roof snow loads.
Contact local building officials for determining required snow loads and a publication can be purchased called ground and roof snow loads for idaho by r.
For roof snow loads not greater than 30 psf the seismic gravity load w need not include the roof snow load.
1 dead loads plus a minimum unit live load of 30 lb ft2 2 months load duration.
The purpose of this web site is to provide ground snow load analysis information and data gathered from all 50 states.
