Because the desired fall may be difficult to achieve in practice the designer may need to adopt a design fall considerably steeper often twice than the recommended finished fall.
Flat roof fall building regs.
How are flat roofs defined.
With regard to fall protection requirements applicable to the construction work itself 1926 501 b 10 low slope roofs requires conventional fall protection a combination of a monitoring system and warning line or on roofs of 50 feet or less in width a monitoring system alone i e without a warning line be used.
40 units in length for every one unit drop in height although the minimum fall required according to bs 6229 a british standard for flat roofs is a shallower 1 80.
If flat roofs are to work well they have to have a slope known as a fall to shed rainwater.
Here are some basic ideas for developing fall protection strategies for roofing operations.
The building regulations encourage a minimum fall of 1 40 i e.
To enable compliance with the requirements of the building regulations to be demonstrated full details of the new roof will be needed including materials and their dimensions and performance properties.
Flat roof this usually consists of felting which has a slight fall to allow rain water to drain off.
There are several methods of building in a fall.
Part h of the building regulations regarding drainage state that water should drain to one or two edges.
Protecting roofing workers 5.
What pitch is a flat roof.
Occasionally a new flat roof will be required to replace an old roof for example asbestos or corrugated tin roofs which are either not allowed under building regulations or are in a complete state of disrepair.
In bs 6229 a roof is defined as flat if it has an overall pitch of 10 degrees or less.
According to bs 6229 bs 8217 flat roofs should be designed with minimum falls of 1 40 to ensure a finished fall of 1 80 can be achieved allowing for any inaccuracies in the construction.
When installing or repairing a flat roof you must adhere to building regulations.
There is also the scope to incorporate a green roof onto the flat structure.
The building regulations for flat roofs can seem like a lot to understand which is why we have put together a simple guide of the things you need to know about when it comes to considering the building regulations for flat roofs.
A qualified roofing contractor will be able to advise on this but here are some of the main guidelines.
Regulations and the general duty clause.
Cover photo courtesy of the national roofing contractors association.
It is a requirement of building regulation part h that adequate provision is made for rainwater to be carried from the roof of the building.