Key Roofing Terms for Godalming Homeowners
Flashing
Strips of lead, zinc or other metal used to waterproof junctions between the roof covering and walls, chimneys or other penetrations. In Godalming, lead flashings are the most common type and typically last 40–60 years before needing replacement due to thermal fatigue.
Ridge Tile
The shaped tiles that cap the apex where two roof slopes meet. Traditionally bedded in mortar, modern dry ridge systems use mechanical clips instead. Ridge tiles are the most wind-vulnerable component on any Godalming roof.
Breathable Membrane
A synthetic sheet installed beneath roof tiles and above the rafters. It allows water vapour to escape from the roof space while preventing rain penetration. Replaced traditional bituminous felt in modern roofing specifications.
Nail Sickness
Corrosion of the nails holding slates or tiles to battens, causing them to lose grip and slip. Common on Victorian and Edwardian slate roofs where original iron nails have been in service for over 100 years.
Soffit
The horizontal board that closes the gap between the wall face and the outer edge of the roof. Provides ventilation openings for the roof space and protects rafter ends from weather. Available in uPVC or timber.
Bargate Stone
A distinctive honey-coloured sandstone found in the Godalming area, quarried locally until World War II. Properties built with Bargate stone require lime mortar for repointing — cement mortar causes moisture trapping and irreversible spalling damage.
GRP Fibreglass
Glass Reinforced Plastic — a seamless flat roofing system created by laminating glass fibre mat into liquid polyester resin. Creates a jointless waterproof surface lasting 20–25 years. The preferred system for small flat roofs in the Godalming area.
EPDM Rubber
Ethylene Propylene Diene Monomer — a synthetic rubber membrane used for flat roofing. Applied in large single sheets to minimise joints. Handles thermal movement well and lasts 30+ years. Preferred for larger flat roof areas.