Waterproofing Quantity Calculator
Calculate waterproofing material quantity needed for a roof, terrace or wall area.
About this calculator
Waterproofing failures are expensive to fix after the fact, and under-applying material because of a quantity estimate that ignored the coat count is one of the more common causes of a coating that doesn't actually hold up against monsoon rain or standing water. This calculator multiplies your surface area (roof, terrace or wall) by the number of coats specified for the product, then divides by the coverage rate stated on that product's packaging to estimate total material required in kilograms. Enter area, number of coats and coverage rate, and get a ready-to-order quantity instead of calculating coats-times-area-divided-by-coverage by hand for a job where under-ordering has real consequences. Because coverage rates and recommended coat counts vary significantly between waterproofing product types, cementitious, liquid membrane, or bituminous, always use the manufacturer's specific figures for the product you're actually applying rather than a generic default.
Worked example
800 sqft, 2 coats, 20 sqft/kg coverage
Result: Material required = 80 kg
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