Roof Dead Load Calculation Example

However in my practice i typically use the horizontal run of the roof for both types of load.

Roof dead load calculation example.

Weight psf 20 ga metal deck 2 5 waterproof membrane with gravel 5 5. 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. L r l o r 1 r 2. 15 psf x 14ft 210 pounds per lineal foot.

Where d is floor dead load. 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. 6the 0 6 reduction factor on d is intended to apply to the calculation of net overturning stresses and forces.

Roof live load reduction. Technically you should use the actual rafter length when adding up the weight of roofing materials. 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. 50 psf x 14ft 700 pounds per lineal foot.

For wind the analysis of overturning should also consider roof uplift forces unless a separate load path is designed to transfer those forces. 910 pounds per lineal foot. Load types loads used in design load equations are given letters by type. Used but they typically defined the load cases or combination stress or strength limits and deflection limits.

Roof live load may be reduced by the following equation. Typical unit area dead load calculations. 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.

A table of roof material weights including sheathing insulation and other decking materials.