Roof Dead Load Calculation Example

11 04 2014 computing the unit dead load for a region of surface area generally starts by identifying the region of a roof plan floor plan or elevation where the unit load is needed then looking at a typical section of that area to see how it is constructed.

Roof dead load calculation example.

Typical unit area dead load calculations. 6the 0 6 reduction factor on d is intended to apply to the calculation of net overturning stresses and forces. Used but they typically defined the load cases or combination stress or strength limits and deflection limits. Example roof truss analysis 3 6 stability determinacy assume that truss is externally statically determinate for gravity loads num forces 33 3 36 num eqns 18 x 2 36 therefore stable determinate dead load roof ceiling wt.

Where d is floor dead load. D dead load l live load l r live roof load w wind load s snow load e earthquake load r rainwater load or ice water load. To do this i use conservative too heavy dead loads and full snow loads regardless of pitch. Where l r shall not be less than 12 psf and not more than 20 psf.

R 1 1 for a t less than or equal to 200 psf r 1 1 2 0 001 a t for between 200 psf and 600 psf. For dead loads you are correct. 50 psf x 14ft 700 pounds per lineal foot. Roof live load reduction.

A table of roof material weights including sheathing insulation and other decking materials. 910 pounds per lineal foot. 3 3 dead loads dead loads consist of the permanent construction material loads. Load types loads used in design load equations are given letters by type.

Weight psf 20 ga metal deck 2 5 waterproof membrane with gravel 5 5. 15 psf x 14ft 210 pounds per lineal foot. L r l o r 1 r 2. Roof live load may be reduced by the following equation.

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.