Details on Emergency Overflow
Information about the dialog Emcy. overflow: …
Allows you to specify if and how many spouts should be used in the attic to dissipate over-five-minute-long rainwater event.
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Emergency overflow in attic (EN 12056-3)
Enabled: Water spouts are used to discharge over-five-minute-long rainfall events in the attic and the input and display fields of the dialog are activated.
Qty. of emcy. overflows
Allows you to adjust the number of emergency overflows as needed. Depending on the number of drain outlets, the capacity of the individual drain outlets (Single capacity Qnot) and the required width of the drain outlets () are displayed.
Height up to overflow edge hDA, Overflow height ho, Water storage level hmax
The Height up to overflow hDA cannot be changed arbitrarily. Numerical values smaller than 55 mm are not permitted, as the prescribed minimum water height of 55 mm at the siphonic drain has to be met. The emergency overflow should not be activated before the reference rainfall is exceeded. Furthermore, the Height up to overflow hDA is permitted to a maximum of 10 mm below the Water storage level hmax. This is related to the assumptions and validity conditions of the design equation for emergency overflows. If the Overflow height ho is less than 10 mm, the width/height ratio is too different.
The dimensions Height to overflow edge hDA and Water stowage level hmax are dimensioned from the height node roof low point.
Total width b of emcy overfl., Width b of an emcy overflow
The total width of all overflows and the width of the individual overflows depending on the number of overflows are displayed.
Total capacity Qemcy, Single capacity Qemcy
The total capacity required for discharge and the single capacity of the drains, which depends on the number of drains, are displayed.