Lead Flashing
(16 Products)The term "lead flashing" refers to the use of lead as a material to seal and protect vulnerable areas of a building from water infiltration. Flashing, in this case, refers to the process of installing lead strips or sheets along seams, joints, and other gaps in the structure - such as where the roof meets the wall or around chimneys - where water is most likely to enter. The name "flashing" is derived from the action of the lead itself, which is expertly shaped and fitted to “flash” or divert water away from these critical areas. Lead is chosen for its ability to mould easily around irregular shapes and its durability, ensuring that water is effectively redirected off the building and away from potential trouble spots.
What Is Lead Flashing?
Lead flashing is an essential component in construction, providing long-lasting weatherproofing solutions for roofs, chimneys, and other vulnerable junctions. The term "lead flashing" refers to the process of installing strips of lead around joints and seams in a building’s structure to prevent water penetration.
Flashing is typically used in places where two different surfaces meet, like where a roof meets a wall or where a chimney joins the roofline. By directing water away from these vulnerable areas, flashing helps protect the underlying structure from potential damage caused by prolonged exposure to moisture.
Why Lead?
Lead, a dense and malleable metal, is uniquely suited for flashing due to its physical properties. Known for its low melting point and exceptional malleability, lead is easy to shape and form into the precise angles and curves needed to provide a seamless barrier against water.
Unlike more rigid materials, lead can flex and bend without cracking, making it an ideal choice for areas that experience thermal expansion and contraction due to temperature changes. Its ability to expand and contract with minimal stress helps prevent gaps and ensures a long-lasting, leak-proof seal.
In addition to its flexibility, lead also forms a natural protective layer called patina. This occurs when lead reacts with environmental factors like air and moisture. Over time, the metal develops a dull grey or greenish coating, which protects the surface of the lead from further corrosion. This patina serves as a barrier, preventing the metal from deteriorating when exposed to harsh weather conditions, like rain, snow, or pollution. The protective layer helps the lead retain its strength and effectiveness, ensuring that it continues to perform well in waterproofing applications for many years.
Applications
Lead flashing is commonly used in a variety of roofing and construction applications, including:
- Chimney Flashing - Seals the junction between the chimney and the roof, preventing water penetration.
- Valley Gutters - Directs rainwater safely off the roof.
- Dormer Windows - Ensures a waterproof connection between the window and roof structure.
- Abutments & Roof Junctions - Provides a secure seal where different roof sections meet walls or other structures.
- Bay Windows & Conservatories - Offers enhanced protection against water ingress in exposed areas.
Types Available
We stock a range of lead flashing products, including:
- Code 4 Lead Flashing - A versatile and widely used lead flashing thickness, ideal for most domestic roofing applications.
- Code 5 Lead Flashing - A thicker, heavier-duty lead sheet suited for areas requiring enhanced protection and longevity.
Rolls & Sizes
Our selection includes various widths and weights of milled lead flashing rolls to suit different project requirements. Popular sizes include:
- Code 4 Lead Flashing - Available in widths ranging from 150mm to 600mm, supplied in 6m rolls.
- Code 5 Lead Flashing - Available in widths from 390mm to 1200mm, supplied in 6m rolls.
Benefits
- Durability - Lead flashing has an exceptionally long lifespan, often exceeding a century with the correct maintenance.
- Flexibility - Its malleability allows for easy shaping and fitting, even in complex roofing structures.
- Weather Resistance - Withstands extreme weather conditions, including heavy rain, frost, and strong winds.
- Aesthetic Appeal - Enhances the traditional look of period properties while complementing modern architecture.
Frequently Asked Lead Flashing Questions
How Long Does Lead Flashing Last?
Lead flashing can last for over 100 years if well-maintained. The material’s resistance to corrosion, flexibility, and the protective patina it develops make it a long-lasting solution for waterproofing in both residential and commercial construction.
Why Should Mortar Joints be Raked Out When Installing Lead Flashings?
Mortar joints should be raked out to a depth of at least 25mm to allow the lead flashing to be securely inserted and wedged in place. This helps minimise the risk of water penetration and ensures a solid connection between the flashing and the wall or roof structure.
How Much Overlap Is Needed When Joining Lengths of Lead Flashing?
When joining multiple lengths of lead flashing, the overlap should be at least 100mm. This ensures a continuous waterproof seal and helps prevent water from bypassing the flashing.
Can You Integrate Lead Flashings With Roofing Underlay?
Yes, lead flashings are designed to work seamlessly with roofing underlay. Typically, the underlay is folded up a minimum of 100mm behind the flashing at abutments, creating a robust barrier that prevents water from infiltrating the roof space, even during heavy rain or strong winds.
Can You Connect Lead Flashing To A Cavity Tray?
You can. When flashing intersects with a cavity tray, the mortar should be raked out to a depth of 25 mm below the cavity tray. This allows the flashing to be properly tucked in, preventing water from bypassing the flashing and entering the wall cavity.
Is Professional Installation Recommended For Lead Flashings?
Yes, it is highly recommended to have lead flashings installed by professionals with experience in working with lead materials. Correct installation is critical to ensure that the flashing is correctly shaped, fitted, and integrated with other building components for maximum effectiveness.
