Long-term outdoor weathering of PVC siding

Observations of white and grey PVC siding weathered outdoors for periods of up to 11 years indicate that the exposed surfaces chalk after two to three years. Weathering induces slight changes, or none, in the tensile properties at yield of both white and grey; tensile strength at break of white siding decreases moderately, whereas that of grey siding does not change significantly. The elongation at break of both white and grey siding decreases markedly in the first five years, but little in the following six years.