Fittings and fixings
Ridge and hip tiles from lengths
- where
- ridge tiles
- total ridge length (m)
- effective cover length per tile (mm)
- hip tiles
- number of hips
- length of each hip (m)
- total ridge and hip tiles
Explain this equation
Counts ridge and hip tiles from the lengths of ridge and hips. Use it alongside the main tile count when ordering.
Lengths are in metres, so 1000 converts them to millimetres to compare with the cover length e, which is the length each ridge or hip tile covers once lapped or butted. The ridge is rounded up once; each hip is rounded up on its own and then multiplied by the number of hips, because you cannot share a part tile between hips.
Simple division of a run by the cover per unit, rounded up.
Sense check: a 2 m ridge with 450 mm cover needs 5 tiles; four 6.31 m hips need 15 each, so 60, giving 65 in all.
Watch out: add hip irons, end caps or ridge-hip junction pieces separately, and allow some spares for cuts.
Ridge and hip tiles needed: each run divided by the cover length of one tile, rounded up per run because offcuts rarely carry from one hip to another.
Enter your values to see the result.
Good to know
Common segmental and half-round concrete ridges are about 457 mm long, butt-jointed. Dry ridge and dry hip systems have their own effective length, unions and end caps: use the system data. BS 5534 requires every ridge and hip tile to be mechanically fixed even when bedded in mortar. Mortar-bedded hips need a hip iron at the foot of each hip.
Common mistake
Adding all the hips together before dividing, which under-counts by up to one tile per hip.
Limits
Straight runs. Junction pieces (three-way and four-way), stop ends and hip end tiles are extra items.
Sources
- Marley segmental concrete ridge tile, 457 × 248 mm (merchant product data)
- Marley: What are the fixing requirements of BS 5534? (all single-lap, ridge and hip tiles mechanically fixed; perimeter tiles fixed twice)
- BS 5534:2014+A2:2018 Slating and tiling for pitched roofs and vertical cladding. Code of practice (BSI)
Results are calculations from the published methods and figures shown, and depend on the data you enter. Follow the roof covering manufacturer’s fixing specification, BS 5534, BS 8000-6, BS 6229, the Lead Sheet Training Academy guidance and Building Regulations. Wind uplift and structural design need a competent designer.