In figuring the quantity of siding required for a structure, it is necessary to increase the footage by an amount sufficient to compensate for the difference between nominal and finished sizes. Additional amounts must also be added for the machining of joints and the overlap in beveled siding. Below the calculator is a table of the approximate percentages that should be added to the net square footage of wall surface to be covered: The calculator below is added for your convenience.

 

*for eaves add an extra 10%

*area for gable ends can be calculated by multiplying the height above the eaves by the width and dividing by two.