Lead Flat Roof Construction Details

Wood core roll as used on ridges hips and flat roofing wood core roll is to be used to allow for the expansion and contraction in lead sheet and flashing.

Lead flat roof construction details. The basic construction of a flat roof starts with roofing timber that is laid across two upright items usually two walls. Thicker lead is used on longer bays joints along the length should be stepped to prevent rain seeping up through capillary action. N gives a permanent flexible and waterproof joint. N designed for lead masonry and lead brick pointed work.

Wood core roll is used for joining bays of lead roofing also on steeply pitched roofs and lead cladding where a bold joint appearance is preferred. However it is important to follow the basic principles of sizing and fixings as indicated in the rolled lead sheet manual to reduce the effects of fatigue cracking or creep. 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. When a hot roof surface is suddenly cooled by rain the pressure in.

N avoids problems of cracking and lack of adhesion associated with mortar joints. Lead detail lead is commonly is used as a means to complete and help maximise the efficiency of a roof s water sheddings qualities. Traditional lead roof coverings are normally weathertight but not watertight. Lead for the purpose fitting to a roof or bay window really starts at code 4 in theory if the roof is small enough you could use code 3 but this would normally be classed as a flashing lead i e.

For additional stability you can also use steel joists that are built into one or both of the walls. N neutral cure product. N recommended by the lead sheet association. Small over flashings or leak soakers.

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. N cleaner quicker and easier to use than mortar with high adhesion to both lead and masonry. Lead should be laid in bays sections with joints between the bays formed over a wooden roll. An acid cure will give rise to white tains on the lead s n life expectancy of 20 years.

For roof detail the gauge of lead to be used will be dependant upon the application. Flat lead roofs should be laid with a slight fall. Our basic fitting guides are designed to assist installing rolled lead sheet in a range of roofing applications including flashings valleys gutters and flat roofing. It invariably can be found in a number of locations on a roof s profile and it s main function is to channel and deflect rainwater.

It is shaped to prevent wind lift.