Find the right gutter size - this is how it works!

The roof area is not the same for every building, so the size of the gutter cannot be the same either. We show here how to find the right channel size for your own home in order to keep damage away at the same time.

Which gutter size for which roof area?

If a semicircular gutter in the standard dimensions is used, the following sizes or diameters should be used.

  • Also read - The most important companion of the gutter: the right downpipe
  • Also read - The gutter's best friend: the right downpipe
  • Also read - Renewing the gutter yourself

If you use two downpipes for a gutter, you only need to consider half the area of the roof when making your calculations. When in doubt, it is always a good idea to make both the gutter and the downpipe a little larger.

  • Roof area up to 25 square meters - 70 millimeters gutter
  • Roof area up to 50 square meters - 100 millimeters gutter
  • Roof area up to 100 square meters - 125 millimeters gutter
  • Roof area up to 160 square meters - 150 millimeters gutter
  • Roof area over 160 square meters - at least 125 millimeters gutter plus two downpipes

Box gutter holds more water

A box gutter takes in a little more water than a semicircular gutter. The box gutter is a possible solution, especially if the roof area that is to be drained lies on the border between two gutter sizes.

With existing roof drainage systems, the gutter brackets also have to be replaced when square box gutters are attached.

  • Roof area up to 25 square meters - 60 to 70 millimeters gutter
  • Roof area up to 50 square meters - 85 millimeters gutter
  • Roof area up to 100 square meters - 100 millimeters gutter
  • Roof area up to 160 square meters - 120 millimeters gutter
  • Roof area over 160 square meters - at least 100 millimeters gutter plus two downpipes

Attach the downpipe according to the channel size

Similar to the gutter, the downpipe is also adapted to the size of the roof area. The same applies here: the angular version absorbs a little more water compared to the round version of the same size. Here you can expect a ten to 15 percent higher water intake.

  • Roof area up to 25 square meters - 60 millimeters gutter
  • Roof area up to 50 square meters - 80 millimeters gutter
  • Roof area up to 100 square meters - 100 millimeters gutter
  • Roof area up to 160 square meters - 100 to 120 millimeters gutter
  • Roof area over 160 square meters - at least two downpipes required
Tips & Tricks On a modern house, a standard gutter in the semicircular shape looks slightly old-fashioned and therefore ruins the look. So if you want to modernize your house a bit, you shouldn't forget the gutter and rather install a stylish, angular box gutter.