Roof & Gutter Details
Plan area draining to gutters
Default: 100 mm/hr
5% typical
Results
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NAIBC / IRC codes
References & Sources
Standards Cited
- IPC / UPC — International/Uniform Plumbing Code
Gutter and downpipe sizing for roof drainage
Formulas Used
- Required flow rate:
Q = roofArea × rainfallIntensity / 3600
Source: IPC / UPC — Q in litres/second, area in m², rainfall in mm/hr - Number of brackets:
brackets = ceil(gutterRun / bracketSpacing) + 1
Source: IPC / UPC
Key Assumptions
- Design rainfall: varies by location (default 100 mm/hr / ~4″/hr) — IPC / UPC
- K-Style gutters: 5″ and 6″ standard profiles — Industry standard
- Bracket spacing: 30″ (762 mm) maximum — Industry standard