Geometry · not design
Yu Lai's Calculator
Give it any two of span, height, rafter length or pitch — it solves the other two, live.
Single span
Multi-span bays
Inputs
Units
mm
cm
m
ft-in
Run — span
Rise — height
Length — rafter
Pitch
degrees
1:x ratio
% slope
Enter any two values.
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Rafter profile
Run
—
Rise
—
Rafter length
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Pitch
—
Degrees
—
Ratio
—
Percent
—
Bays
Bay
Run
Pitch °
Slope
Rise
Rafter length
Apex height
Totals
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—
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Roof-line profile