Live And Dead Load For Residential Roofs

The total dead plus live loads equal the gravity load of the structure.

Live and dead load for residential roofs.

The values for dead loads in table 3 2 are for commonly used materials and constructions in light frame residential buildings. It is important to list live load dead load and total load separately because live load is used to compute stiffness and total load is used to calculate 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. These dynamic loads may involve considerations such as impact momentum vibration and etc.

15 psf x 14ft 210 pounds per lineal foot. Natural and engineered wood rest relatively lightly on the foundation but support less live loads than steel and concrete. 910 pounds per lineal foot. 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.

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. Building materials are not dead loads until constructed in permanent position. 50 psf x 14ft 700 pounds per lineal foot. Structural steel offers much less of a dead load and provides superior support for live loads in multi story buildings.