Our Canvas is rot/fire and waterproof.     The pattern used for the Yurts makes for a perfect fit, and the seams are all interlocking for strength and are all sewn simetrically to not spoil the order of the roof.   A star cap can be pulled over the smokehole for those rainy days and nights and makes the Yurt watertight and really cozy!   allaboutyurts@ymail.com