Load limits on the roof of a building.
Live load for roofs in kentucky.
Roof live loads largest roof loads typically caused by repair and maintenance pitch rise span lr 20 r1r2 12 lr 20 lr horizontal projection roof live load 16 r 1 r 2 live load reduction factors r 1 accounts for size of tributary area of roof column a t r 2 effect of the roof rise.
A great deal of confusion currently exists among engineers architects recreation specialists and maintenance personnel concerning the proper snow loading to use for the design and maintenance of trail bridges building roofs and other structures in mountainous high snow load areas.
Ordinary flat pitched and curved roofs and awnings and canopies other than of fabric construction supported by lightweight rigid skeleton structures are permitted to be designed for a reduced roof live load as specified in the following equations or other controlling combinations of loads in section 1605 whichever produces the greater load in structures such as greenhouses where special.
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.
If you live in the us our snow load calculator compares the total weight on your roof with the permissible load calculated according to the standards issued by the american society of civil engineers regarding the minimum design loads for buildings and other structures asce7 16.
Other considerations for sloped roofs can be found throughout chapter 7 of asce 7 10.
In our case let s assume that our structure has a flat roof roof slope 5.
Flat roof snow loads p f the snow load that is applied to our structure is not the ground snow load but in most cases the flat roof snow load.
The roof shall be designed for the live load indicated in table r301 6 or the snow load indicated.
Underlayment materials required to comply with astm d226 d1970 d4869 and d6757 shall bear a label indicating compliance to the standard.
Underlayment for asphalt shingles clay and concrete tile metal roof shingles mineral surfaced roll roofing slate and slate type shingles wood shingles wood shakes and metal roof panels shall conform to the applicable standards listed in this chapter.
2attic loads may be included in the floor live load but a 10 psf attic load is typically used only to size ceiling joists adequately for access purposes.
In order to stay intact and in place a roof must be able to resist loads both permanent and temporary that are pushing.
However if the attic is intended for storage the attic live load or some portion should also be considered for the design of.
Why snow load information.
Victor staley a building official in the town of brewster mass responds.
