Davis Langdon鈥檚 article on the costs of metal roofing (Specifier, July, page 13) missed an important point.

While it is true that base metal prices vary, data from the 黑洞社区 Cost Information Service shows that an increase in roofing cost of 拢1/m2 adds only about 0.1% to overall building cost. This low sensitivity greatly reduces the impact of metal price fluctuations so that the choice of roofing finish can be based on other criteria such as aesthetics and sustainability.

Sandy Harrison, chairman, Copper in Architecture

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