How to Set the Ridge on a Gable Roof with Unequal Wall Heights

Unequal wall heights on a gable roof? That's an unequal match with the Construction Master Pro. It'll calculate that answer before breakfast 🧠

#roof #framing #carpentry

[Oldhogleg]

For those without them there fancy high falutin calculators, you can do the same thing with a simple pocket calculator by the following formula:

Ridge distance from high wall = [(Total span x pitch rise ÷ pitch run) - wall hight difference] ÷ [(total span x pitch rise) ÷ pitch run]

Or:

Ridge distance from high wall = (Sr/R-Δ)/(Sr/R)

S=total span: 20ft
r=pitch rise: 8in
R=pitch run: 12in
Δ=wall hight difference: 3ft

Or more simply:

Ridge distance from high wall = Stanθ-Δ/Stanθ

Where: tanθ = r/R = 8"/12"