J Hempstock & Co Ltd has a team of specialist operatives for lead work encompassing sheet and decorative work particularly in the Heritage sector.
Lead was historically used for roofs because it is a perfect protective roofing material no matter which elements it is exposed to. Reacting with oxygen, water and the carbon dioxide that is naturally in the air, it forms a white surface film of lead carbonate and this is the main reason that it is such a durable, long lasting construction material. However, roofs have to sustain the presence of rotting leaves, bird droppings, lichen and sometimes the growth of moss all of which contribute to acetic damage such as corrosion. This means that lead roofs should be regularly cleaned.
Lead is also a soft metal and prone to mechanical damage particularly during the winter when lead pipes get blocked and exposed to frost. If water in the pipes becomes frozen it is likely to split them during the expansion process and then when it thaws, leaking can cause some seriously expensive problems with the ensuing damp.
The joints on the collars of lead downpipes should be open so that if the pipe becomes blocked there is somewhere for the water to escape. It also makes it simple to see where there is a blockage in the pipe.