Lead sheet has been a key component of Leeds roofs, and roofs around the country for a long time. According to the Lead Sheet Association (LSA), about 70% of the lead sheet currently produced is used for flashings and weatherings on roofs – protecting vulnerable joints in buildings, such as where roofs abut walls.
The advantages of lead sheet as a roofing product are that it is long-lasting, weather-resistant and malleable, which is important as flashing and other details need to be formed around the contours of the roof and joints in buildings.
Abutments
Roofs can be particularly vulnerable to damage and water ingress at junctions such as where walls meet pitched roofs or bay window roofs.
For this reason all abutments should be weathered using lead.
Soakers are used where a slated or double-lap plain tiled pitched roof abuts a wall. They are normally made from code 3 lead sheet.
Flashing should be tucked into a mortar joint with a minimum depth of 25mm and at least 100mm above the roof tiling level for step flashing. To avoid damage to damp-proof courses (DPCs) and cavity trays, the joint for lead flashings should be raked out as work proceeds. The joint should then be pointed in cement mortar.
Alternatively, the flashings can be built in as the work proceeds. They should be built in to a depth of 50mm and a welted edge should be provided to form a key with the mortar. Cutting out the joint once the mortar has hardened is likely to cause damage to DPCs and cavity trays, leading to water penetration.
Flashings or soakers should also be used where there is a change in roof slope of 5° or more.
Soakers or a secret gutter should be installed at abutments where slates, flat interlocking tiles or plain tiles are used.
If you need maintentance work or repairs carrying out to the roof of your home or business then contact Leeds roofers DPR Roofing on 0113 3470916 or email us at [email protected]