A Brief Introduction To Lead
In the ever-changing construction industry, lead has been an ever present for 100s of years, thus showing its strength in the industry, with churches, historical buildings, and country houses having used lead on their roofs for centuries. In part, this is due to lead’s versatility, longevity, flexibility, and recyclability.
Global economies need to work towards lowering their carbon dioxide emissions and reducing waste and landfill. As such, all the lead that we use is 100% recycled material. We even recycle our lead offcuts and waste material so that others can benefit from reusing the planet’s natural materials. Lead also has the lowest CO2 footprint amongst other metal roofing materials, such as zinc and copper (Midland lead, 2019)(1).
Lead Sizing and Errors
Lead comes in a couple of different forms but has many applications available. The main form that lead comes in is called “rolled sheet lead” and this is the form that is most commonly used. We can purchase lead in various roll sizes and thicknesses, known as Codes. The Code of lead corresponds to the mass (lbs) per area (sq. ft): Code 4 lead weighs 4lbs per square foot. The differing thicknesses allow for lead rolls to be used for a multitude of purposes. However, due to the natural expansion and contraction of lead, different sizes of lead are only appropriate for certain applications. In addition to the usage chart (below), lead bays also have a maximum length and width.
Oversizing of lead has been one of the most common errors that we see when problems arise with existing leadwork. Oversized (or over-fixed) lead does not allow for the natural movement caused by the expansion and contraction of lead. Within the UK, the changing weather conditions and temperatures make this more prevalent. Eventually, this will cause the lead to split and tear, resulting in water ingress. Due to this, the Lead Sheet Association has a set of maximum recommended sizes of sections, bays and panels, with them stating that “oversizing may cause failure”. For example, the maximum length of lead that you can use for a flashing is 1.5m (regardless of the code of lead used).
In addition to lead being extremely functional, it also has the possibility of being highly decorative. Lead flashings can be scalloped and curled to create an aesthetically pleasing finish on vertical tiling. We can also cast lead to form decorations. Casting lead decorations involves pouring molten lead into an impression made in sand. Once this has cooled, the sand can be brushed off, and the edges filed and cleaned to create a neat finish. We have used this technique in the past to make roses, finials, swirls, fleur-de-lis, and even a gremlin’s face. This helps us to match in with existing work, or to match heritage and historical work. Similarly, lead can be decorated via welding beads of lead to create lettering or numbers and has been used to add a date to some of our work.
Leadwork in Surrey and West Sussex
At White and Sons Ltd., we are trained in the traditional methods of leadwork, using hand-tools to dress and boss the lead to form the required shape, and welding lead where required. We take pride in our work and the skill set that our employees have, and have been carrying out high quality leadwork in Surrey and West Sussex for over 30 years. You can also rest assured that White and Sons Ltd carry out all our leadwork to current British Standards (BS6915) and to the recommendations of the Lead Sheet Association. If you have any leadwork requirements, please do not hesitate to contact us or visit our lead page.