Flat roofs covered with felt, asphalt, lead, copper, zinc and aluminium were considered in earlier Detail Sheets.

ASBESTOS-CEMENT ROOFING

Asbestos-cement is manufactured from asbestos and portland cement. The material is reasonably strong, durable, noncombustibleand light in weight. It is resistant to alkalis and most acids, although a higher degree of acid pollution in the atmosphere may affect it. If properly sealed or primed the material may be painted and this will assist preservation in unfavourable situations. (Sheets are available coloured by factory applied processes, which have a high resistance to fading and wear).