Calculation to determine the drainage capacity

The professional dimensioning of emergency overflow systems is essential for the durability and safety of your flat roof solutions.

Determine the drainage capacity depending on the water level in the pipe:

Round Emergency Overflow Drains / Parapet Drains

Flow Rate Q [l/s]

Rectangular Emergency Overflow /Parapet Drains

Flow Rate Q [l/s]

Pressure height in round and rectangular emergency overflow / parapet drain

The water pressure height [mm] is essential for the drainage capacity. The higher the pressure height, the greater the drainage capacity. To determine the pressure height, the maximum allowed water level on the roof must be known.