PVC (polyvinyl chloride), commonly referred to as Vinyl, roof membranes have the longest track record of any thermoplastic membrane,with the first PVC-based systems installed in the early 1960s. PVC is a molecule comprised of carbon, hydrogen and chlorine (taken from salt).
Reinforced vinyl membranes have a long history of installations worldwide; many that were installed over 20 years ago are still performing today. Robison Roofing is an authorized contractor of the leading PVC roof system manufacturers - Sika Sarnafil and IB Roof Systems.
PERFORMANCE
Reinforced PVC roof membranes have many important attributes that complement their proven track record. Besides the important feature of heat-welded seam technology, PVC or vinyl roof membranes offer many other inherent features, including:
- A comprehensive history of product testing
- An ability to be made in a spectrum of colors including reflective white
- Highly resistant to puncture and impact
- Excellent resistance to flame exposure and subsequent fire propagation
- Proven durability against rooftop soiling and contamination
- Good low-temperature flexibility and high-temperature tolerance
THE PVC ADVANTAGE
Thermoplastic roofing membranes are typically formulated with a combination of PVC resins, stabilizers, plasticizers, fire retardants, and pigments. Sika Sarnafil brand PVC blends these components to produce consistently high-quality roofing products that stand alone in providing customer satisfaction and protection.
Almost 40 years ago, the polymer chemists at Sarnafil engineered what are now recognized as the longest-performing thermoplastic roofing and waterproofing membranes in the world. The basic formulation that has protected buildings for all these years is still used today.
Vinyl is the best known thermoplastic roof membrane. “Thermoplastic” means that when heated sufficiently, the material temporarily changes from a solid to a semi-solid state enabling the sheets or panels that are overlapped to be fused togetherand return to a solid upon cooling, yielding one continuous membrane. It is this feature that enables the seam overlaps of vinyl roof membranes to be fused ("heat welded") together.
FAQ
- What is PVC?
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Specifically, PVC is “polyvinyl chloride”, or more commonly known as vinyl. PVC is a molecule comprised of carbon, hydrogen and chlorine (taken from salt). As mentioned above, today’s reinforced vinyl membranes have a long history of installations worldwide; many that were installed over 20 years ago are still performing today. Vinyl membranes for roof applications were first developed in Germany and Switzerland in the 1960s and arrived in North America in the 1970s. The use of vinyl membranes in low-slope roofing has grown significantly and rapidly in North America ever since then.
- How does PVC compare to other roofing systems?
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Expansion and contraction, ponding, moisture, thermal shock, and temperature extremes are all factors that promote premature degradation of a roofing membrane. The great elongation and low temperature flexibility of PVC "vinyl" membrane accommodate building movement in various climatic conditions without stressing the material. Its moisture absorption resistance allows the material to be installed in assemblies with lesser slope than other single-plies and makes it tolerable to incidental ponding and deflection. Due to its ability to withstand extreme temperatures, premature membrane aging is reduced, lengthening the life expectancy of PVC constructed roofing systems.
- What attachment methods are available?
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Vinyl roof membranes have great versatility of application. Depending on your application, Robison Roofing offers vinyl roof membranes to be mechanically-attached or adhered to the insulation/substrate. In addition, vinyl membrane can be readily produced with “fleece cushion” backing (typically polyester) that enables it to be installed over slightly rough surfaces and/or to be adhered with a variety of adhesives.
To complement this versatility of application, vinyl roof membranes can be manufactured in a variety of colors.This feature allows for the application of rooftop logos or multiple-color roofs.
- How is PVC "welded"?
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Vinyl is the best known thermoplastic roof membrane. “Thermoplastic” means that when heated sufficiently, the material temporarily changes from a solid to a semi-solid state enabling the sheets or panels that are overlapped to be fused together and return to a solid upon cooling, yielding one continuous membrane. It is this feature that enables the seam overlaps of vinyl roof membranes to be fused or heat-welded together.
To accomplish the welding, specialized, electrically-powered welding equipment that is either self-propelled or handheld is used. These units operate on electricity and inject heated air into the seam area, softening the membrane surfaces. A roller that is either hand-held or part of the self-propelled unit, presses the seam overlap together. As the welder moves away from a given seam location, the membrane quickly cools down to ambient temperature and the heat weld is made, providing a watertight bond.
- How long do PVC roofs last?
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Countless PVC roof installations have exceeded 30 years of service life. Average service life is 20-25 years.
- Can PVC roofs be repaired?
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The characteristics of PVC "vinyl" roofs are such that, even after years of field service and exposure to the elements, repairs and/or modifications can be accomplished with ease and with the expectation of long-term performance.
MORE INFORMATION
RSI Suppliment (Click to open in new window)
Sika Sarnafil Publications (Click to open in new window)