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Roof Pitch & Rafter Calculator
Convert pitch angle to rise, rafter length and roof area — with rafter counts, ridge, gutter and batten lengths, tile quantities and approximate roof loads.
UK coverage rates · BS 5534 guidance context
5°60°
Common UK pitches
Rise
2.80m
Rafter
5.18m
52 rafters
Roof area
103.7m²
Ratio
1 : 1.4
Timber & linear elements
Rafters @ 400mm centres52 (270m timber)
Ridge board length10 m
Gutter run (eaves)20 m
Fascia board20 m
Batten length332 m
Breathable membrane120 m² (3 × 50m rolls)
Coverings & approx. dead load (incl. waste)
Interlocking concrete tiles (~10/m²)1089 · ~4.7 t
Plain clay tiles (~60/m²)6531 · ~7.8 t
Natural slates (~13/m²)1415 · ~2.9 t
Guide quantities only. Confirm coverage with your tile manufacturer and rafter sizing with a structural engineer. Need full roof drawings? Request a free quote.
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