- Roof pitch can be low, provided that effective rainwater drainage can be maintained.
- Care must be taken to avoid the possibility of ponding on the surface.
- Vents, flues, skylights and other roof penetrations must be sited to avoid restricting the water run-off. This is particularly important on low-pitch roofs.
- Adequate ventilation/insulation should be provided to prevent condensation on soffits.
- 55% Al-Zn should not be used in conjunction with copper or lead. Contact with water run-off from pipes, channels or fixings containing copper or lead must also be avoided.
- 55% Al-Zn should not come into contact with wet timber, wet concrete or wet mortar.
- For optimum performance, all accessories and fastenings should be made from 55% Al-Zn steel, or from stainless or heavy zinc coated steel.
- 55% Al-Zn is not suitable for use in alkaline rich environments, and its use should be avoided in, for example, agricultural buildings for animal housing or organic fertiliser storage.
|
|
|
