Live And Dead Roof Loads In Nc Residential Design

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.

Live and dead roof loads in nc residential design.

Reinforced concrete creates the heaviest dead loads but also supports the most weight with its tremendous compressive strength. Light frame wood roof with wood structural panel sheathing and 1 2 inch gypsum board ceiling 2 psf with asphalt shingle roofing 3 psf 15 psf. Ground snow load commonly 10 psf usually roof live load governs unless snow drifts are considered frost heave. Roofing criteria state of north carolina pat mccrory governor department of administration kathryn johnston acting secretary.

Dead load live load cold weather load. It is intended to advance residential building design by unifying the current practice of applying design loads. Wind uplift pressures c. With tar and gravel.

The might of the dead load or lack thereof often defines how much live load it can handle. Method of determining design loads for typical residential construction in the united states. That a designer may find useful and necessary. Loads used in design load equations are given letters by type.

Live roof load w wind load s snow load e earthquake load r rainwater load or ice water load t effect of material temperature h hydraulic loads from soil f hydraulic loads from fluids. This criteria for roofing design is a compilation of data policies legal aspects preferences experiences prejudices etc. The scope therefore is limited to single family attached and detached buildings. Where uniform roof live loads are reduced to less than 20 psf 0 96 kn m 2 in accordance with section 1607 11 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.

The values for dead loads in table 3 2 are for commonly used materials and constructions in light frame residential buildings. D dead load l live load l. 3 3 dead loads dead loads consist of the permanent construction material loads comprising the roof floor wall and foundation systems including claddings finishes and fixed equipment. With conventional clay tile roofing.