Circular roof outlets are manufactured with a smooth flange where applicators are bonding or mechanically fixing drain connectors to the waterproofing membrane across the face of a flat roof or terrace

The spigot is 250mm long and is inserted down inside of the HDPE drainpipe. This gives ample assurance that no water can back up behind the rubber and onto the deck. The spigot is slightly cone shaped and ribbed. This helps with installation into the hole, and prevents water passing back up behind the spigot.

The mouth of the shank has a series of internal serrations so the gravel guard or leaf excluder can be fitted easily and securely. Remember installers of these outlets will always need to insert leaf guards or gravel excluders (this will be a hyperlink to “accessories” page) into the moth of these connectors to prevent the pipes becoming blocked.

They are positioned throughout the roof deck at intervals approximately 25 – 30m2 apart to handle the amount of potential UK rainwater run-off.  To ensure a proper seal, installers should do the following:

See the CAD images here

INSTALLATION

Waterproof the area around the drainage hole. This can be done either by installing a patch around the area or by waterproofing the entire deck in the normal manner. Insert the correct size of outlet connector into the hole so that it is covering the waterproof membrane. Secure the connector either by using fixings or adhesive.

Then prepare the area for another layer of waterproofing membrane so that the outlet connector is encapsulated in a “sandwich”. To ensure that the second coat of waterproofing bonds properly, the area should be primed. Here a patch of the same type of membrane is installed and adhered across the face of the outlet connector, completely covering the flange and bonding to both it and the first layer of waterproofing membrane beneath. By doing this the water cannot get behind any parts of the connector and enter the structure.

Once the membrane / adhesive is cured a hole may need to be cut to reveal the drain pipe, and a leaf guard or gravel excluder is inserted into the hole. The outlet is then finished.

Above is an example of the circular outlet with a smooth flange, where the surround is bonded to the waterproofing membrane.

H is the height of the spigot or pipe

D1 is the outer diameter of the flange or surrounding ring

D2 is the inner diameter of the pipe at the top

D3 is the inner diameter of the pipe at the bottom

D4 is the outer diameter of the well at the top and also the outer diameter of the leaf guard

The circular / downpipe outlets with smooth flange are available in the following sizes:

Wallbarn code

Category

D1

D2

D3

D4

H

090-040-240-040

Smooth 40mm

235

26

24

31

240

090-040-240-060

Smooth 60mm

235

48

43

53

240

090-040-240-075

Smooth 75mm

320

65

61

70

240

090-040-240-080

Smooth 80mm

320

69

64

74

240

090-040-240-090

Smooth 90mm

320

77

73

82

240

090-040-240-100

Smooth 100mm

320

85

80

90

240

090-040-240-110

Smooth 110mm

320

91

87

96

240

090-040-240-125

Smooth 125mm

320

111

106

116

240

090-040-240-140

Smooth 140mm

380

127

122

132

240

090-040-240-150

Smooth 150mm

380

136

131

141

240

090-040-240-160

Smooth 160mm

380

146

141

151

240

090-040-240-200

Smooth 200mm

380

185

180

190

240

 

Remember installers of these outlets will always need to insert leaf guards or gravel excluders into the mouth of these connectors to prevent the pipes becoming blocked.

We have a range of leaf guards and gravel excluders to further enhance this product.