Gable Roof Calculator

Calculate rafter length and roof surface area for a symmetrical gable roof.

Project dimensions

Building width

Building length

Roof rise

Eave overhang

Rafter spacing

LIVE GEOMETRY · Gable roof geometry

LIVE ESTIMATE

Your results

Rafter length5.06 m

Roof area129.6 m²

Roof pitch32°

Rafter pairs23

Total rafters46 pcs

Practical guidance

Using this estimate

This is geometric estimating, not rafter sizing. A structural professional should determine member sizes, ties, bracing and connections.

Measure the actual project before ordering and confirm product dimensions, pack sizes, structural requirements and local building rules with the relevant supplier or qualified professional.