Roof load calculator

To calculate the weight of snow on a roof , use the first two sections of our snow load calculator. You need to supply the following information: Lengthand widthof your roof. Span Calculator for Wood Joists and Rafters also.

For ground snow loads greater than pounds per square foot, the roof load is equal to of the product of the exposure, thermal and importance factors, the ground snow load , and (pounds). If you have any concerns as you are determining your flat roof snow load , consult with a structural engineer or roofing specialist. Online Snow Load Calculator (for Buildings with Flat or Low Slope Roofs - for Balanced Snow, Drift, and Rain-on-Snow Surcharge Loadings ) calculator (ASCE 7-05) for structural engineers, construction professionals and building planners.

For dead loads , you are correct. Technically you should use the actual rafter length when adding up the weight of roofing materials. However, in my practice, I typically use the horizontal run of the roof for both types of load. To do this, I use conservative (too heavy) dead loads and full snow loads regardless of pitch.

For example, if building is 24′ x 24′ and has trusses, and the load on the roof will be for lb snow load and a ceiling with no storage will total out like this. This will amount to twice as much load on the exterior walls compared to a building with a center wall. This calculator takes all of this into consideration. How do you calculate roof load? How to figure roof loading?

Use the span tables below to determine allowable lengths of joists and rafters, based on size and standard design loads. You can also use the Wood Beam Calculator from the American Wood Council website to determine maximum rafter and joist lengths. Calculate Truss Load The formula for truss loads states that the number of truss members plus three must equal the twice the number of nodes. Loads are contributed to the lower header by the roof , upper walls and 2nd floor system.

The Architectural Graphic Standards lists the weight of an exterior 2×wall as pounds per ft 2. The dead load of a typical asphalt-shingle wood-framed roof is about pounds per square foot. The load increases with the use of heavier roofing material. A clay-tiled roof may have a dead load. The final step in calculating the snow load is to multiply the volume of snow on the roof by its density. If you have a density range, then multiply the volume by each part of the range separately to find the minimum and maximum snow load.

You might also be interested in our snow to water volume calculator. Roof Load Calculator Disclaimer: The calculations on the Rig World site are intended for professional riggers who understand them and know how to interpret the. Neither Ben Kilmer, Rig World or its affiliates make any claims or warranties about the accuracies of the from these calculations.

Continuous Confidence. Any roof load calculator can tell you how much weight your structure deals with at the moment. We take things up a notch by making sure you have the peace of mind you deserve for as long as you use our system. This free roofing calculator estimates the area of a roof and the amount of materials required to replace or build said roof. Click on the appropriate beam, this will take you to the calculation table for your project.

The column on the left of each chart labeled BEAM SPAN represents the beam length (with bearing) required for your project. The top column labled SPAN CARRIED BY BEAM determines the span supported by your beam. Create a Truss Load Diagram. It is a good idea to fill in the resulting numbers from the truss load calculations on your roof truss sketch from the beginning. This will help you keep track of them while installing each triangular truss and it can be a handy reference for which nodes you have assigned as load -bearing, fixe and rolling.

Multiply the load per square foot by the total area of the roof. This number represents the total load that your roof must carry.