Tools and calculatorsGet your bearings before anyone's on a ladder.
These tools help you work out where a leak might be starting, whether to restore or re-roof, whether a quote covers what it should, and whether an old roof could be asbestos. They run in your browser, and nothing you enter is saved or sent anywhere.
Which one should you use?
Water coming in? Start with the leak finder. Tired roof, and wondering what's worth doing? Try restore or re-roof?. Holding a quote? The quote checker lists what a good one includes, so you can tick off what's there and ask about what isn't.
Planning a re-roof or a repaint? The roof area calculator gives a rough size and pitch, handy for sense-checking the measurements on a quote. The COLORSTEEL colour visualiser and our colour pages help you narrow down a colour, though NZ Steel says screens show colour differently from the real product, so look at a sample in natural light before you decide.
Older home? The asbestos checker tells you whether to treat the roof with caution. WorkSafe says the only way to confirm asbestos is to have a sample tested, so a cautious answer is your cue to get a test.
What the tools can't do
Each one gives you a lean, not a diagnosis, and a roofer standing at your place will always see more. When a tool says it's time for someone to look, send us the job and we'll pass it to one checked roofer who covers your area.
Tools and calculators
Where this information comes from
- New Zealand Steel Limited (COLORSTEEL) Colour (COLORSTEEL colour selector, with TSR and LRV for each colour), 28 October 2026
- WorkSafe New Zealand Asbestos in the home (quick guide, last updated 15 August 2024), 28 October 2026
Every fact and rule on this page comes from the sources above, checked on the dates shown. How we write and check these pages.