The Sustainability of Vinyl Roofing Membranes
Vinyl roofs, also known as thermoplastic polyvinyl chloride (PVC) membrane roofing, can improve building energy efficiency while positively impacting the quality of the urban environment. The longevity of vinyl roofing membranes – combined with their relatively low use of non-renewable resources, reflectivity, energy efficient characteristics, suitability for green roof assemblies and recyclability – make them the sustainable choice among commercial roofing systems. The reflectance, emittance and/or solar reflectance index criteria for LEED, ENERGY STAR, Green Globes, and California’s Title 24 can all be met through the use of a reflective vinyl roofing membrane.
WHAT MAKES VINYL ROOFING SUSTAINABLE?
- HIGH REFLECTIVITY – White vinyl roofs achieve some of the highest reflectance and emittance measurements of which roofing materials are capable. A white vinyl roof can reflect 80 percent or more of the sun’s rays and emit at least 70% of the solar radiation that the building absorbs, making it the more sustainable roofing option. An asphalt roof only reflects between 6 and 26% of solar radiation, resulting in greater heat transfer to the building interior and greater demand for air conditioning – a strain on both operating costs and the electric power grid. Net annual energy savings are typical even in northern climates. Cool roofs can have more impact on energy cost than energy use, cutting consumption during peak power demand when the rates are the highest and offsetting any minimal wintertime increases in use when there is less sunlight to reflect.
- REDUCTION IN URBAN HEAT ISLAND EFFECT (UHI) – In full sun, the surface of a black low-slope roof may experience a temperature rise of as much as 50 to 90 degrees, reaching midday temperatures of 150 to 190 degrees in summer. A white vinyl roof on the same building typically increases only 10 to 25 degrees above ambient temperatures, lowering surrounding air temperature and reducing smog formation.
- RECYCLABILITY– Manufacturing scrap from vinyl roofing membrane has long been recycled into new accessory roofing products. But vinyl is the only commercial, sustainable roofing material that is being recycled at the end of decades of service life into the feedstock to make new membranes.
- LONG SERVICE LIFE – While all products have environmental impacts resulting from manufacturing and shipping, vinyl roofing membranes have a long service life that is second to none. Many vinyl roof systems have been in service in excess of 25 years.
- COMPATIBILITY WITH OTHER GREEN ROOFING COMPONENTS – Vinyl can be a component of building integrated photovoltaic (BIPV) solar electric roofing systems because the material’s proven long lifecycle, high reflectivity, superior fire ratings and hot-air welded seams assure that the roofing substrate will function as long as the PV modules. Vinyl roofing membrane is also used in concealed applications such as the waterproofing layer in planted roofs. The permanent hot-air welded seams do not deteriorate in the perpetually moist environment of a green roof, and those same seams provide the highest resistance to root penetration of any waterproofing membrane.
- LOW EMBODIED ENERGY – When compared to other roofing materials, less energy is needed to produce the raw material vinyl and process it into the end product. Most alternatives have far more embodied energy.
- COMPRISED OF RENEWABLE RAW MATERIALS – 57% of vinyl resin is derived from salt. Less oil is consumed to produce vinyl than in the production of base materials for any other single-ply roofing membrane.
References & News
Zero Waste Roofing [1.7 MB]
The Facts on PVC and the Environment [1.5 MB]
PVC roofing membranes can stand up to some of the toughest stresses and have been proven to support and protect roofs throughout the world.
PVC roofing membranes’ aesthetic qualities make them the choice for any roof design.