How Many Ridge Tiles Do I Need?

How We Calculated This

Ridge tiles sit along the apex of the roof. They overlap slightly so the effective cover length is less than the tile length:

• Ridge length: 8m
• Tile length: 450mm, effective cover ~430mm (allowing for butt joints)
• Tiles needed: 8 ÷ 0.43 = ~18.6, round up to 19
• Add 1–2 spares for breakage = ~20 ridge tiles

Common Ridge Tile Types

• Half-round: Most common, suits most tile and slate roofs
• Angular / V-shaped: Modern look, used with interlocking tiles
• Segmental: Matches concrete interlocking tile profiles
• Universal angle: Adjustable angle, fits various roof pitches
• Dry ridge system: Mechanical fix, no mortar needed (BS 5534 compliant)

Dry Ridge vs Mortar Bedded

Since 2015, UK Building Regulations (BS 5534) require mechanical fixingof ridge tiles on new builds and re-roofs. Dry ridge systems use clips, unions, and a roll of ventilated ridge material. Mortar-bedded ridges are still found on older properties but are no longer compliant for new work.

Dry Ridge System Components (per ridge tile)

• Ridge tile clip/bracket
• Union piece (joins adjacent tiles)
• Ridge roll / ventilated membrane (continuous strip)
• End caps (2 per ridge run)

Tips

Measure the full ridge length including any hips. Order 10% extra for breakage. Ensure the ridge tiles match the main roof tile manufacturer and colour. For hip ridges, use the same formula but measure along the hip rafter length.