How To Figiure Gutter Slope

For a simple gable end roof you would only need to make two calculations one for each slope.

How to figiure gutter slope. This means the downspout end of the gutter should be set 3 4 of an inch lower than the other end. Therefore this roof should be equipped with 6 inch k style gutters. First you ll need to calculate the square footage of the gutter s drainage area. Or you can slope the gutters down from each end toward a single downspout placed in the middle of the run.

Use the bubble on the line level to make sure the line is level the length of the gutter area. For gutter runs longer than 40 feet it s best to pitch the gutter down from the middle to a downspout at each end. Determine the longitudinal slope transverse slope and manning s roughness coefficient of the gutter. How to determine gutter slope.

Hip roofs and intersecting roofs have multiple facets. Then fasten one end of the string at the highest point of the gutter and the other at the spot where the downspout will be. Compute the ponded depth and width. Next place a ladder at the left side of the house and measure from the roof down to the gutter.

For those you will need to add up the area of each surface within a drainage area to get the total square footage. Multiplying that number by the local maximum rainfall intensity 6 8 inches per hour yields an adjusted square footage of 7 480 square feet. As a general rule gutter slope is set at 1 4 inch per 10 feet of guttering. Place the line spirit level on the string.

To ensure that gutters drain properly make certain they slope inch for every 10 feet toward a downspout. For example if you have 30 feet of guttering the calculation is 1 4 x 3 0 75 i e. The best way to calculate the slope of a gutter run before hanging it is to use a long string and a string level. For a constant transverse slope compute the ponded depth using equation 10 1 and the ponded width using equation 10 2.

For example if the gutter is 16 feet long the end near the down spout must be 1 inch lower than the starting end.