Roof Dead Load Calculation Example

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.

Roof dead load calculation example.

50 psf x 14ft 700 pounds per lineal foot. Used but they typically defined the load cases or combination stress or strength limits and deflection limits. Typical unit area dead load calculations. Roof live load may be reduced by the following equation.

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. To do this i use conservative too heavy dead loads and full snow loads regardless of pitch. However in my practice i typically use the horizontal run of the roof for both types of load.

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. Technically you should use the actual rafter length when adding up the weight of roofing materials. 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 wind the analysis of overturning should also consider roof uplift forces unless a separate load path is designed to transfer those forces.

L r l o r 1 r 2. 15 psf x 14ft 210 pounds per lineal foot. A table of roof material weights including sheathing insulation and other decking materials. For dead loads you are correct.

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

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.