The slope of a roof is properly known as its pitch and flat roofs have up to approximately 10.
Flat lead roof construction.
Traditional lead roof coverings are normally weathertight but not watertight.
A new lead bay fitted in a simple one piece bay like this one the lead is nailed into the upstand underneath the guttering the drip is then beaten nice and tight over the edge of the roof and trimmed to about 50mm.
The national roofing contractors association defines a low slope roof as.
One of a series of instructional videos produced for the lead sheet association in this case showing how to install a flat roof in lead.
On a basic level flat roof construction comes in the form of roofing timbers or joists as they are more commonly known or steels that are laid across two uprights walls in most cases.
Lead should be laid in bays sections with joints between the bays formed over a wooden roll.
Flat lead roofs should be laid with a slight fall.
Note no nails in the edge.
Flat roofs are an ancient form mostly used in arid climates and allow the roof space to be used as a living space or a living roof.
In general a warm roof is preferable from a construction angle but it does lead to a higher roof profile which isn t always acceptable from a planning perspective there a number of variations of the warm roof referred to as hybrid roofs which introduce different elements.
Thicker lead is used on longer bays joints along the length should be stepped to prevent rain seeping up through capillary action.
For additional stability you can also use steel joists that are built into one or both of the walls.
Investigative work carried out on warm roofs covered in lead has shown that in rare instances moisture can also be introduced by the development of sub atmospheric pressure in the roof space.
A flat roof is a roof which is almost level in contrast to the many types of sloped roofs.
The steels or rsj s rolled steel joists are often built into one or both walls to give added stability to the roof structure.
When a hot roof surface is suddenly cooled by rain the pressure in.
Flat roofs or low slope roofs are also commonly found on commercial buildings throughout the world.