The right gutter drain guarantees reliable drainage


For a functioning water drainage system, the gutter must have the right size and the drainage nozzles and the diameter of the downpipes must be correctly dimensioned. In addition to the roof area and shape, the expected precipitation plays an important role.

Size ratios and distances

The gutter outlet consists of the drainage connections to the downpipes, which are either Einhangstutzen or gutter boxes. They run conically funnel-shaped and accelerate the flow rate of the water.

Important are the dimensions of the gutter drains, which must match the size of the gutter. This applies to both the nozzles and the diameter of the downpipes. Another basis for fast and reliable water drainage is the number and spacing of each drain point.

As a rule of thumb, in gutters in normal dimensions for private buildings of gutter drains at a distance between 1.50 and 1.80 meters is assumed. A possible inclination of the channel course and the shape play an additional role.

Standard sizes and installation types

When the gutter size has been calculated according to the roof area to be drained, the appropriate and sufficient diameters for the downpipes are assigned.

  • For the selection, the classifications of the nominal sizes, which are defined according to the European standard DIN EN 612, apply.
  • The standard diameters for downpipes are sixty, eighty and one hundred millimeters. The more drain points are installed, the smaller the diameter can be selected.
  • Hooks are simply hooked into correspondingly cut holes in the groove and fixed by means of jamming.
  • Channel boxes are connected to the gutters laterally and are often used as decorative elements with small ornaments.

Price examples per piece

As with the gutters themselves, the material used to make gutters plays the main role in pricing.

  • In dachrinnen-shop.de, the pre-weathered titanium zinc hanger for semicircular gutters is offered, depending on size, between around 14 and 30 euros each.
  • At hbw-handel.de there is an aluminum connecting spout in four sizes between nine and 14 euros each.
  • At fink-klempnereibedarf.de, copper connecting pipes are offered between eight and 16 euros each.

Tips & Tricks

In order to secure the gutter drain even in the event of blockages and dirt, plastic siphons are suitable, which are placed on the drain sockets.


Video Board: How to Drain Downspout Water Flow Away from a House