installation workers . If this problem can be solved, fibre-cement seems to be the major green alternative to PVC for affordable mass-produced siding. Another challenging area for substitution is pipingincluding tubing, conduits, and pipe fittingswhich accounts for almost half of PVC sales. Most of this consists of municipal water and sewer pipes, outdoor drainage pipes, and industrial and agricultural pipes. Two types of PVC pipes are everyday residential construction materials: the DWV (drain/waste/vent) plumbing inside buildings, where use of PVC has become the norm; and electrical conduits, where PVC competes with steel. As in the case of siding, there are high-quality alternatives, but they are not so widely available as the mass-produced vinyl pipes. Clay pipe is more than suitable for underground sewage and water pipes, with a common life span of 100 years and a high resistance to chemicals in wastewater. In the UK, high density polyethylene (HDPE) pipes have been found to be more flexible and shock-resistant (Greenpeace Australia, 2003). Both polyethylene and metal pipe can be used in DWV applicationswith Philadelphias Sheraton Rittenhouse hotel (billed as North Americas first eco-smart hotel) using black metal drainpipe for approximately the same cost as PVC (Ackerman, 2002). Economic strategies for PVC substitution involve two key interrelated dimensions: (1) ramping up market demand for safe alternatives that can increase economies of scale and therefore decrease production costs, and (2) implementing various forms of extended producer responsibility (EPR) that reflect the full lifecycle environmental costs of PVC production. Because of the fundamentally unstable nature of PVC and organochlorines, real EPR should ultimately mean the complete banning of