If you collect roof run-off in a tank and use it for drinking water, you’ll need to be careful about how you clean and maintain the roof. You’ll also need to steer clear of some roofing materials.
When you’re washing the roof, disconnect the downpipes so you don’t send contaminated water into your tank.
Products not suitable for collecting drinking water are:
- Any lead-based products.
- Asbestos cement.
- Wood treated with CCA (copper, chrome and arsenic) or LOSP (light organic solvent preservative).
- Bituminous materials.
The following products need washing or weathering before they are suitable:
- New, untreated cedar.
- Newly applied acrylic roof paint.
- Fibre cement products.
The following products can be used straight away (as long as they are clean):
- Galvanised steel.
- Clay tiles.
- Factory-painted steel or tiles.
- Stainless steel.
- Mineral fibre asphalt.
- Butyl (although black butyl rubber will need regular maintenance and cleaning as it weathers).