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Home Glossary Verge
Roofing noun

Verge

/vurj/

Also known as: gable verge, verge detail, verge trim, gable edge

The edge of a roof at a gable end, where the roof covering overhangs or meets the gable wall. The verge detail must be weathertight and secured against wind uplift, typically using a mortar bedded verge, dry-fix verge system, or bargeboard with undercloak.

On older properties verges are often mortar-bedded, which can crack and allow water ingress. Dry-fix verge systems using purpose-made plastic or aluminium trim are now preferred under BS 5534 for wind uplift resistance. The verge typically projects 50mm beyond the gable wall.

Approved Document A - Structure

Wind uplift standardBS 5534:2014+A2:2018
Minimum overhangTypically 50mm
Dry-fix preferredYes - mortar alone not adequate

BS 5534 requires all roof tiling and slating, including verge details, to be mechanically fixed. Mortar-only bedding is no longer considered adequate for wind uplift resistance.