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Advertising supplement provided by Duradek

Waterproof PVC roof deck and flooring systems are highly durable and maintainable with periodic washing to remove surface dirt. Rougher membranes may require washing with a scrub brush and mild detergent or pressure washing. Regular inspection of caulking and immediate attention to any loose seaming will ensure that the PVC membrane lasts for years to come.

Detailing refers to the workmanship involved in installing materials and assemblies such that they are watertight and aesthetically appealing. Permanent secure waterproofing depends upon proper detailing at perimeters and penetrations. “A good or bad detail can often mean the difference between a good and a bad installation,” says Ogilvie, noting that use of pre-manufactured flashing details for outside corners, posts, and railing attachments can help ensure a neat and waterproof detail. Good workmanship and proper detailing are critical to the long-term performance of a waterproof outdoor flooring system, and should always be installed by manufacturer-approved and/or trained technicians. PVC membranes can be hot-air welded to provide a completely waterproof seam, making them well-suited to fine detailing. Poor workmanship and improper detailing will compromise deck aesthetics, and will result in poor deck performance. “The manufacturer provides a lot of good details to ensure a watertight installation as well as providing the required fasteners and accessories,” says Robbins.

Deconstruction refers to the use of waterproofing solutions that offer long-term life expectancy as well as ease of replacement. Deconstruction is a relatively new concern that has become increasingly important for "green" construction. In terms of durability, with proper care and cleaning, today's waterproof PVC membranes can be expected to last for 10 to 15 years or more—and 20-25 years is not unusual. Demountable flashing systems are one way to reduce the amount of deconstruction required to repair or replace a waterproofing membrane. These systems are easy to remove, and allow the PVC membrane to be repaired or replaced quickly and easily with minimum destruction. Membrane and trim panels can be replaced without disrupting the existing wall system and doors, which means that to replace the waterproofing membrane, one doesn’t have to take off the siding or stucco or compromise the second waterproofing job.

Installation Considerations

Like all products, the PVC membrane will function more effectively with proper installation. Well before the product hits the deck, a thorough examination of the space that will be covered is in order. The better the surface, the better the finished floor. In a typical installation, the vinyl is installed over the top of the structural plywood flooring. Code requires 5/8 inch plywood, but 3/4 inch provides a stronger surface with less bounce and less warping. If the plywood is of poor quality, pressure-treated or it is oriented strand board, it must be overlayed with a plywood or cement board skin. Since 1/4 or 3/8 inch plywood usually warps, an overlay of no less than 1/2 inch is recommended.

Sanded plywood or cement board will give the best-finished surface possible. As a rule, 1/4 inch or 3/8 inch plywood will warp due to absorption of moisture from the atmosphere. For the flattest possible surface, it’s recommended to overlay with minimum 5/8 inch and preferably 3/4 inch plywood. In any case, the deck must be secure, well supported, clean, smooth, free of depressions, waves and projections, properly sloped to drains, valleys, or eaves.

Duradek is a multinational company that has installed over 100 Million Square Feet of 100% waterproof, vinyl membranes since 1974. This decking system was developed in the Pacific Northwest, a place that relies on superior waterproofing products for its harsh climates. Not only does Duradek perform well in all kinds of weather, it also comes in over 20 colors and patterns to enhance the exterior of any home. It is a non-slip, mildew resistant, outdoor flooring, with a life span of approximately 20 years. Besides being an exceptional decking membrane, Duradek Ultra products may be used over living space to provide a dry, watertight area below. It is ICC approved for use over habitable areas and also carries Class A and C fire ratings.