How to Calculate Urethane Waterproofing Quantity
Urethane waterproofing quantity is calculated by multiplying application area × number of coats × coating thickness × product density. For example, 500 sq ft × 2 coats × 40 mils at 11.6 lb/gal density yields approximately 20 lbs net. Add 10% for waste and losses, then round up to the nearest pail size.
Typical application rates for roofs and balconies are 40–60 mils per coat, applied in 2 coats. Critical areas like drains, corners, and penetrations often require additional reinforcement and extra material.
Always apply a compatible primer to properly prepared concrete before the waterproofing membrane. Most manufacturers require primer for warranty coverage. Ambient temperature should be above 40°F during application and cure.
Frequently Asked Questions
Urethane waterproofing bonds well to concrete, masonry, metal, and primed wood. It's used on roofs, plaza decks, parking structures, and below-grade walls.
Properly applied urethane systems typically last 10–20 years. UV-stable topcoats and regular inspection extend service life significantly.