21
Wavin AS+
Technical Manual
4.3. Functional requirements
The dimensional specifications of waste water standards are based on various requirements:
The loss of trap water resulting from the flow of water must not reduce the total level of the water seal
by more than 25 mm in height.
The trap water must not be sucked out by a vacuum or expelled by excess pressure.
The nominal dimensions of waste water and mixed-water systems must not exceed those specified in DIN 1986-100.
The waste water pipeline must be self-cleaning.
The following sizing method applies to all gravity waste water drainage systems designed to dispose of domestic waste water. The
layouts of industrial and commercial waste water drainage systems used in such places as swimming pools or factory buildings
must be designed individually. Performance figures are based on the minimum internal diameters specified in the table in DIN EN
12056-2.
Please note that the product standards applied to pipes and fittings used in Germany are based on outside diameters, which might
lead to certain deviations with respect to the tables in DIN EN 12056.
Minimum fall
Compliance with the required minimum fall is vital for the proper drainage of waste water. Waste water standards specify different
minimum falls, depending on the piping area concerned
Nominal diameter (DN) with corresponding internal diameter
Di
min
as per Table 1, DIN 12056-2 (extract).
Tabel 2: Minimum fall for waste water pipes in different piping areas.
Nominal diameter and diameter used by Wavin AS+.
Nominal diameter
Minimum internal diameter
DN
Di (mm)
50
44
70
68
90
79
100
96
125
113
150
146
200
184
Area of piping
Minimum fall
Standard/section
Unventilated connection pipes
1%
DIN EN 12056-2, Table 5
DIN 1986-100, Section 14.1.3.3
Ventilated connection pipes
0.5%
DIN EN 12056-2, Table 8
Underground and collector pipe and collecting pipes
DIN 1986-100, Section 14.1.1+14.1.5
a) Waste water inside the building
0.5%
DIN 1986-100, Section 14.2.7.3
b) Waste water outside the building
1: DN
Nominal diameter
Minimum internal diameter
DN
Di (mm)
50
44
70
68
90
80,8
100
99,4
125
114,4
150
148,8
200
188
