All products have some negative environmental impact and PVC is no exception.
Never theless, PVC offers exemplary environmental performances. Probably the most critically important consideration in material selection is energy and resource efficiency.
In the continuing drive to reduce the weight of materials and improve insulation, plastics - and PVC in particular - provide solutions which traditional materials cannot. Plastics contribute less than 0.5 per cent (by weight) of all construction and demolition waste and their use has dramatically reduced the overall weight of buildings (and hence the overall quantity of waste).
Safety statistics for the PVC manufacturing industry are better than the chemical industry average, which itself compares favourably with other sectors.
Published life-cycle studies, conducted in accordance with ISO standards, demonstrate that PVC holds a favourable ecological position in its main markets. It has a low dependency on non-renewable resources, low embodied energy and a correspondingly low contribution to carbon dioxide levels, compared with alternatives. Durability, lightweight and energy-saving attributes of PVC products in service are also important considerations.
The PVC industry is only 50 years old and it is still undergoing rapid development. Recent advances in the manufacture of PVC pipes include twin-walled design with corrugated outer layers, foamed core pipes, and biaxial orientation of the pipe walls. These innovations are providing reductions in PVC pipe weights of up to 60 per cent compared with traditional plain compact wall pipes, without compromising performance. Other developments are multi-chamber window profiles and foam filling, which reduce heat transmission and, as a result, improve insulation for window profiles and cladding.
New PVC cable formulations have exceptional fire performance properties.
And automated separation and mechanical recyling technologies have been developed for all major PVC building products.
Philip Law is director of public affairs at the British Plastics Federation. Tel 020 7457 5000
In 1995, a pioneering office block project was completed at Newcastle upon Tyne's Northumbria University. Jointly funded by the UK government, the EU and ironically Greenpeace, the block was the UK's first solar-powered office block. The south wall was covered with 21,000 solar cells and 646 PVC window profiles.
Worldwide production of PVC is now 20 million tonnes per year.
However, production uses less than 0.3 per cent of all annual oil consumption due to its low dependence on non-renewable resources.
Most PVC building products have a long lifespan - up to 100 years in the case of pipes - and require virtually no maintenance.
Under typical fire conditions, PVC will resist ignition for much longer than other materials, will not spread flame and will often self-extinguish when a flame source is removed.
When PVC products do catch fire, they burn very slowly. In terms of smoke obscuration and toxicity, PVC is in the middle of the range for all organic materials.
The manufacture of pressure piping for the building, construction and transportation industries in the US requires more than 56,000 trillion fewer BTUs of energy than iron and concrete/ aggregate alternatives.Also, because PVC pipe and fittings are lighter in weight than alternative materials, they save further energy in transportation. Research by Franklin Associates of the manufacturing process for PVC and aluminium windows determined that PVC used about three times less energy.
Reinforced PVC roofing membrane has scored more than 104 on a scale of 1-100 in the solar reflective index of relative reflective and thermal emissive performance properties of roofing surfaces. This capability helps structures to stay cool in summer, reducing the need for air-conditioning. PVC is also an excellent thermal insulator, reducing heat loss from the structure in winter.