If you’ve ever had a roofer mention flashing and wondered what they were talking about — you’re not alone. Roof flashing is one of those terms that gets used a lot but rarely explained. Here’s everything you need to know.What is Roof Flashing?Roof flashing is thin strips of metal — usually lead, aluminium or zinc — that are installed at joints and intersections on your roof to prevent water getting in. Wherever two surfaces meet on a roof there’s a potential weak point where water can penetrate. Flashing seals those weak points and directs water away from vulnerable areas.Where is Flashing Used on a Roof?Flashing is used in several key areas on a typical UK roof. Around chimneys — this is one of the most common places flashing is used. Lead flashing is fitted around the base of the chimney where it meets the roof to prevent water running down between the chimney and the tiles. Around skylights and roof windows — flashing seals the edges of roof windows to prevent leaks. In valleys — where two roof slopes meet there is a valley which channels rainwater. Valley flashing or a lead lined valley directs this water into the gutters. Around soil pipes and vents — any pipe that comes through the roof needs flashing around it to keep water out. At abutments — where a roof meets a wall, flashing is used to seal the joint.What Does Flashing Look Like?On most UK homes flashing is made from lead and has a dark grey colour. You’ll typically see it as a strip of metal running along the base of a chimney or around the edge of a roof window. Over time lead flashing can develop cracks, lift away from the surface or have its joints fail — all of which can lead to leaks.How Long Does Flashing Last?Lead flashing is extremely durable and can last 50 to 100 years if installed correctly. However the mortar or sealant used to fix it in place typically only lasts 10 to 20 years and may need repointing or resealing before the lead itself needs replacing.Signs Your Flashing Needs AttentionThere are several signs that your roof flashing may be failing. These include damp patches on ceilings near chimneys or roof windows, water stains on walls near chimney breasts, visible gaps or cracks in the flashing, flashing that has lifted away from the surface, and mortar around the flashing that is crumbling or missing.Can Flashing Be Repaired?In many cases yes — flashing can be repointed, resealed or partially replaced without needing a full replacement. We always assess the condition of the flashing carefully and give honest advice on whether a repair or full replacement is the most cost effective solution.Get a Free Flashing Inspection from Cole RoofingIf you’re concerned about your roof flashing or have noticed any of the signs above, Cole Roofing offers free roof inspections across Pershore, Evesham, Worcester, Cheltenham, Oxford and surrounding areas.Call us on 07586 407635 or email info@coleroofing.co.uk to book your free inspection today.