Flat Roof Drainage System Design

To help see where any water might be collecting clean any debris from the flat roof surface including sweeping or gathering fallen leaves or branches and clearing any loose debris or gravel that may block drainage holes.

Flat roof drainage system design.

Flat roof design guide some bauder waterproofing systems are bba approved for use with zero falls but back falls are not acceptable and should be corrected. The most critical of these issues is the flat roof drainage systems. If it hasn t that s a sign of a problem with roof drain parts or the drainage system. In order to ensure a finished surface with zero fall a design fall of 1 80 should be used and a detailed structural analysis should account for construction tolerances settlement and for deflection under load.

Along with the benefits of a flat roof come unique challenges. It is important for architects plumbing engineers and civil engineers to work together to design a system that will properly drain rainwater from a building and site. I examined several roof drainage calculators and tables to see what they tell us. Buildup of rainwater on a roof can cause structural damage and leaks.

While a proper drainage system design is essential for the overall reliability of the roof a quality installation ensuring the design is implemented properly is key. Interior drains are the most expensive flat roof drainage system. Improper gutter drainage can cause erosion of soils and foundation issues. To design a sloped or flat roof drainage system we need to know the anticipated maximum rainfall rate and the flat or projected roof area.

The roof drainage outlets and rainwater downpipes are calculated based on the design principles for gravity drainage systems established in ss525 2006 code of practice for drainage of roofs. Please see roof drainage calculations for a detailed answer to your question. Before deciding on an interior drain system for your flat roof you must consider the following disadvantages. More attention should be given to the location of a drainage system to avoid future problems.

The calculations below are meant for drainage from flat roofs where water are expected to spread over the entire flat roof during rain. Of course the best designed flat roof has the correct amount of pitch to drain the water off naturally. Flat roof drains scuppers gutters and drainage systems on flat roofs one of the most overlooked items on a flat roof is the draining system.