Chimney draft and diameter calculator
Chimney sizing helper
The tool helps compare draft and section values during early design checks.
Fire safety and equipment manuals always take priority over this simplified estimate.
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Use the calculator to turn input values into a clear, repeatable result.
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Keep units and assumptions visible so the calculation can be checked later.
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Copy the result or key numbers for reports, messages or spreadsheets.
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Reset to defaults when you want to compare another scenario from a clean state.
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Calculators run in the browser and are useful for quick estimates before formal checks.
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For finance, health, engineering or legal decisions, verify important results with a specialist or official source.
