Rain gutter - only with the perfect gradient a success

The gutter should keep water and dirt away from the building. But in addition to the right size, which must match the size of the roof surface, the slope should be calculated exactly so that the gutter can clean itself.

Self-cleaning of the gutter by incline

Many experts recommend a slope of one millimeter per meter for a gutter. However, other craftsmen emphasize that the self-cleaning function of the gutter only starts at a gradient of five millimeters per meter of gutter.

Therefore, it is important to plan the gap sufficiently large, because you save a lot of work at the same time. After all, not only leaves but also leaves of birds and the moss from the roof land in the gutter.

If the slope was chosen too low, you would have a real biotope in the gutter within a very short time.

Calculation of the gradient

If one chooses a gradient of five millimeters per meter of gutter length, this is only ten centimeters for a gutter of 20 meters.

Comparison of the slope strengths

While it's easy enough to figure out the gradient on your own, you really have to keep in mind the very small differences that actually result in a drop of one or five millimeters per meter of gutter.

Therefore, here again clearly the slope strength at the different dimensions

  • A fall of one millimeter corresponds to one centimeter at ten meters of gutter length
  • Gradient of three millimeters corresponds to ten inches of gutter three centimeters
  • Gradient of five millimeters corresponds to five centimeters at ten meters gutter length

Tips & Tricks

If you want to install a clear slope of five millimeters per meter of gutter, it may be visually and technically better to provide the gutter with two downpipes.

As already described fall with a length of 20 meters rain gutter ten inches of slope. Since it is visually better to either attach downpipes at both ends or incorporate a large downpipe in the middle.

Video Board: French Drain Tips - Setting slope for Drain pipe - (part 3)