Importance of Gutter Slope

Gutters prevent a lot of bad things from happening, such as basement flooding, a cracked foundation and “bald” spots in the landscaping closest to your home. Gutter slope, also known as gutter pitch, is an important factor in guiding water from the roof, through the gutter channel and into the downpipes where it can safely exit the gutter system.

Basic Rules of Gutter Slope

When standing on the front lawn or in the back yard looking up at the gutters, they usually appear like they run the width of your house in a straight line just below the edge of the roof. But in reality, for the system to function optimally, the gutters should slant one-quarter inch for every ten feet of guttering.

There should be one downspout for every 30 to 40 feet of gutter, depending on the configuration of the roof. When the home’s exterior is 40 feet or more, one downspout on either end is advisable. This means that the centre of the run is the “high” point, with the gutters on one side sloping downward to the left-hand downspout, while the gutter sections on the right-hand side slope toward the second downpipe.

Maintaining Gutter Slope

Proper gutter slope is essential in maintaining the health of your gutters. While it might seem that clogs or blockages are the number one reason for malfunctioning gutters, the source of the problem might be improper gutter slope. When gutters are level or do not slope enough, standing water can invite mosquitoes, plant growth, and debris buildup. If the gutter system is weighed down by water and organic materials, gutter sections can shift, altering the pitch of the gutters.

Gutter slope can also be affected by time. As the gutter system ages, fasteners and nails become loose and begin to pull away from the fascia. Regularly cleaning and repairing the gutters will help reduce conditions that might alter the gutter slope.

Test for Proper Gutter Slope

When gutters and downspouts are in good working order, but there is still standing water in the gutter channel, something’s not quite right. You can test for proper gutter slope by:

  • using a ladder safely (and avoid leaning it directly against the gutters)
  • start measuring at the opposite end of the downspout
  • make a mark every ten feet
  • stop when you’re within three to five feet of the downspout
  • measure the distance between the top of the gutter at the starting point (higher) and the top of the gutter near the downspout (lower) – there should be at least one-inch difference

If you don’t intend on adjusting the gutters yourself, testing first will let you know if you need to call a gutter professional.