Waterproof sails require similar design considerations as shade sails except they are significantly more complex. The vinyl used for waterproof sails must be computer patterned by an appropriately qualified person. Again, the vinyl is available in a wide range of colours, varying degrees of sunlight penetration, and with warranties ranging from 10 to 15 years. Waterproof shade sails require substantial steel posts and footings which can be costly, especially when combined with the cost of the fabric, computer patterning, engineering certification and building approval. Regardless, waterproof sails provide a unique roofing system which can be extremely pleasing to the eye. We also offer Dellor Membrane systems which can be more cost effective (per square metre) than waterproof sails.