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Alumasc's Harmer his roof outlets have revolutionised the drainage of rainwater from large roof areas, typically low-pitched metal roofs with valley gutters. Designed for use with existing or new non-syphonic managed pipe systems, the his system's self-priming flow outlet will operate at 90 per cent capacity without breaking into negative pressure. Compatible with cast-iron or pvc pipework, the system reaches full efficiency at water depth of only 35mm, alleviating the load problems ...

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