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Made in NZ · For NZ buildersRafter spans to NZS 3604
Rafter and purlin spans for the pitch, roof load and wind zone — then carried into the full roof take-off and the priced quote.
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Roof framing, sized to NZS 3604
Rafter spans in New Zealand come off NZS 3604: the timber size and grade, the spacing, the roof load (light vs heavy roof) and the wind zone all change how far a rafter can go before it needs a bigger member or a purlin. Reading it off the tables for every pitch and span is slow.
Toolie takes the roof from a plain-English description or a PDF plan, sizes the rafters, purlins and ridge to NZS 3604 for the load and the wind zone (which it derives from the site address), runs the rest of the roof take-off and prices it off a real NZ pricebook.
- Rafter and purlin spans to NZS 3604 for the load and pitch
- Wind zone derived from the site address
- Light vs heavy roof handled
- The whole roof take-off, not just one span
- Priced off a real NZ pricebook with regional rates
It’s part of the quote, not a separate tool
In Toolie this isn’t a one-off calculator — it feeds the actual priced quote and the build programme. Describe the job or drop in a PDF plan and Toolie runs the take-off, applies NZ site intelligence and prices it off a real NZ pricebook.
More on-site calculators
See all 16 builder calculators, the full feature guide, or how Toolie quotes a job.
Common questions
How far can a rafter span under NZS 3604?
It depends on the timber size and grade, the spacing, the roof load (light or heavy) and the wind zone. Toolie sizes the rafters and purlins to NZS 3604 for your roof and site rather than you reading the tables by hand.
Does it include purlins and the ridge?
Yes - the take-off covers rafters, purlins, the ridge and the rest of the roof framing, sized to NZS 3604.
Does it price the roof?
Yes - Toolie prices the roof framing and the rest of the job off a real NZ pricebook with regional rates.
Quote, comply and get paid — in one place
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