A hip rafter (Dutch ‘hoekkeper’) is the diagonal rafter that runs over the external corner where two roof slopes meet. It forms the sharp arris (hip) of the roof. Below are examples of where hip rafters occur.
Examples in practice
- Hipped roof — the four corners where the roof slopes meet are formed by hip rafters, running diagonally from the ridge to the eaves corner.
- Pyramid (tent) roof — four hip rafters meet at a single point at the top; there is no horizontal ridge.
- Half-hip (jerkin head) — a small hip with two short hip rafters sits above the gable.
- Dormer with a hipped roof — even a small roof on a dormer has hip rafters at the front corners.
Difference from the valley rafter
Note the difference from the valley rafter: that sits in the internal corner (the valley), where water collects. The hip rafter sits at the external corner (the hip), where water runs off to two sides.
Points of attention
- The hip rafter is longer than the common rafters and carries the abutting rafters of both slopes, so it must be of heavier section
- At the hip the roof covering is finished with a hip tile or a cut slate
- A sound, watertight finish of the hip is important to prevent rain penetration
Related terms
- Hip rafter
- Rafter
- Valley rafter
- Hipped roof
- Pyramid roof
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