How exactly a fall is built in largely depends on how the flat roof is built.
Flat lead roof build up.
The fixing of lead sheet is carried out in many different ways all of which are dependent on the particular application.
In the case of a flat roof insulation is usually either a rigid board above the deck or a mineral glass wool quilt immediately above the underdrawn ceiling depending on the type of roof design and construction.
Additionally the build up of ice no matter what the pitch of your roof produces cracks that grow over time which can cause a number of problems for homeowners.
Some carry warranties of up to 20 years approaching those for sloped roofing.
The steels or rsj s rolled steel joists are often built into one or both walls to give added stability to the roof structure.
Also known as the built up roof bur this type of flat roof features three or more layers of waterproof material mixed in an alternating fashion with hot tar and a layer of smooth stone like gravel.
The recognised flat roof build ups for best design practices are.
Fortunately modern materials for covering flat roofs have improved considerably over the past two decades.
The cheapest and simplest solution is to construct a warm roof.
From there the flat roof system you choose will determine the materials you apply.
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.
In terms of the thermal design of a flat roof what are the options and the best practices of flat roof build ups.
Lead is commonly used for flat roofs because of it s long life and ability to be formed to fit many positions.
Underneath the basics flat roofs are usually constructed with a ceiling nailed to joists which support a deck usually wood in residential construction a vapor barrier insulation and a roof board.
As you might imagine this is the cheapest version possible and good for covering a shed.
Lead must be laid and formed correctly to achieve this long life however.
For instance a lead bay on a roof with a pitch of up to 3 degrees differs in the arrangement and position of its fixings when compared to the same bay on a higher pitch.
There are three main choices.
If you build and flash one right and keep it clean a good flat roof won t leak says toh general contractor tom silva who had seven different flat roofs.
How to build a flat roof.
More about lead as a building material correctly laid lead roofgreyfriars roofingnote the height of steps between bays the rolled joints and adequate overlaps.
