wavin OSMA Rainwater - Page 9

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Table2:RoofOutletCapacity
Outlet Diameter Maximum roof area
Outlet mm m Litres per second
3S414 82 143 2.97
4S414 110 209 4.35
Flat Roofs
• Forroofswithapitchlessthan10º:theE�ectiveRoof
Areaforthepurposesofowcalculationissimplythe
planareaoftheroof.
• Fordrainageviagutterspositionedatroofperimeter:
RefertoTable3belowtodeterminewhethersystem
capacityissucientforareatobedrained.
• FordrainageviaWavinOsmaatroofoutlets:Referto
Table2below.
RoofOutletspositionedinthecentreofaatroofcan
drainlargerareasthanoutletslocatedattheedgeor
corneroftheroof.Itisgoodpracticetohaveaminimum
of2atRoofOutletsperroofifnooverowpointhasbeen
designed.
BS EN 12056: Part 3: 2000 7.3.1.
ForreferencetoStandardsseepage86.
Table3:GutterFlowCapacity(l/s)
Running outlet at END of gutter
Running outlet at CENTRE of gutter
Stopend outlet at END of gutter
System
Gutter laid
level
Gutter laid
at fall 1:600
Gutter laid
level
Gutter laid
at fall 1:600
Gutter laid
level
Gutter laid
at fall 1:600
RoundLine 1.30 1.65 2.63 3.40 1.25 1.25
SquareLine 1.40 1.99 3.10 3.71 1.30 1.30
StormLine■
2.44 2.70 4.74 5.28 1.32 1.32
StormLinel 2.39 2.60 4.60 4.98 1.26 1.26
DeepLine 2.38 3.01 5.10 6.21 – –
SuperLine 2.10 2.52 4.30 5.19 – –
RoofLine 2.48 3.41 4.74 6.59 – –