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Note:This Program is free to use, and is based on the Australian Plumbing Code AS/NZS 3500.3:2021. However it can be used for any Plumbing Code.
Find out how
This is a simplified version of the other box gutter calculators.
There is no allowance for vertical faces or rain shadow effects.
However the user can allow for vertical faces by adding
half the vertical area to the catchment area.
By not allowing for rain shadow effects, rain is assumed to be coming
from all directions at once. This may result in a slightly larger box gutter.
However this effect is insignificant for flattish roofs, or small vertical faces. Legend: Boxes shown like this are results. No input needed.
Get a copy of the calculations to AS3500 for your records.
Shows calculation steps and Code references. It allows insertion of Job numbers, Descriptions, etc.
and is designed for printing out on letterhead. Includes all 'Extra features' plus calculates for flows greater than 16L/s.
Activate all programs on this site, including the DP and box gutter printouts, the CSIRO for straight gutters, and all extra features.
Plus get referrals from those looking for your expertise in your area.
More Extra Features.
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Disclaimer: It is the users responsibility to unsure that the program is suitable for their roof configuration,
and that data is entered correctly, according to accepted practice and the attached instructions.