The Roof Coating Calculator computes the number of pails (5 gal) needed to coat a flat roof.
INSTRUCTIONS: Choose units and enter the following:
- (W) Width of Flat Roof
- (L) Length of Flat Roof
Pails of Coating (P): The calculator returns the number of pails of roof coating needed. It also returns the square feet of the roof surface. However, this can be automatically converted to compatible units via the pull-down menu.
The Math / Science
The surface area of a roof is measurable. Pails of coating (as pictured) specify the number of square feet they will cover. The product shown lists a range of 350 ft2 to 500 ft2 for one 5 gallon pail over masonry and roof surfaces. The Roof Coating calculator computes the surface area based on the width and length and divides the surface area by the high an low range to give the user an idea of how many pails of sealer that will be needed for the job.
The formula for Roof Coating is:
`P = (L*W) / (PC)`
where:
- P = Number of 5 gallon pails needed coat a roof
- L = Length of Flat Roof
- W = Width of Flat Roof
- PC = Pail coverage (low: 350 ft2 per pail. high: 500 ft2 per pail)