glossary Glossary 2 min read

Hip rafter

A hip rafter runs diagonally from the ridge end to the external wall-plate corner, carries the jack rafters, and is sized from AS 1684's own hip/valley tables.

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A hip rafter is the diagonal rafter that runs from the end of the ridge down to the external corner of the wall plates in a hip roof. It forms the sloping external corner where two roof planes meet, and it carries the jack rafters that frame into it from each side (per AS 1684.2:2021).

Because a hip rafter carries compound loads from two roof planes meeting at an angle, AS 1684 sizes it from a separate hip and valley rafter span table, not the common rafter table. A hip rafter is usually deeper than the common rafters in the same roof, owing to the extra load and the compound bevel cut at each end.

MemberWhere it runsLoad
Common rafterWall plate to ridgeSingle plane
Hip rafterRidge end to external plate cornerTwo planes (compound)
Valley rafterRidge to internal (re-entrant) cornerTwo planes (compound)

Common defect: sizing a hip rafter off the common rafter table. Hip and valley members have their own AS 1684 span table section; using common-rafter sizes undersizes the hip and risks deflection or failure under the combined load.

Hip rafters belong to conventional (cut-and-pitch) roof framing. Prefabricated truss roofs form hips with girder trusses and hip-end truss sets instead.

Also known as: hip.

See also


Last updated: 2026-05-24. Verified: 2026-05-24. Quarterly review for currency.