Adjusting for pitch and rainfall.
How measure gutter size.
Then use the chart below to see what size gutter you need.
How do you calculate gutter size.
Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted.
See photos below most residential gutters will measure approximately 5 inches across the top with the actual opening being approximately 4 5 inches.
How to measure downspouts.
Multiply drainage area by 1 3.
The steeper a roof s pitch the more windblown rain it can collect.
5 inch 5 520 square feet.
Measure your gutter across the top from the back where the gutter meets the home to the outer edge.
You can also work with a professional who knows the climate in your area and who understands what size of gutter you need to work with the roof that you have.
Measure length of twine mark the measurement with a piece of tape and then pull the twine off of the other end of the gutter.
As a general rule egutter recommends for roof areas that exceed 2800 square feet a 6 k style size with a 3 x 4 downspout size would be appropriate.
Use your tape measure to determine the length of the twine marking down this calculation.
Find the width of the gutters.
If your gutter is 5 inches wide or less you ll need our 5 inch kit.
Calculating the drainage area of a roof.
Gutter size is determined by measuring across the top of the gutter to help you understand gutter measurement and dimensions here is a relative comparison in size between 2 3 inch downspouts vs.
Place a sturdy 20 ft 6 1 m ladder on 1.
Move the tape measure so its blade is sitting plumb against the end of the level.
Which size of gutter guard by gutterglove do you need.
How to measure gutters method 1 of 3.
If a roof s various drainage areas call for different size gutters go for the biggest one k style.
5 inch standard k style gutter shop 5 gutterbrush.
3 4 inch downspouts likewise a comparison between 3 inch round downspout and 4 inch round downspout.
Download our free gutter guide for more helpful information.
7 and greater are appropriate for churches and larger commercial buildings.
6 inch 7 960 square feet.
Hold an extended tape measure at the end of the level that is not touching the surface of the roof.
Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted square footage.
Place a sturdy 20 ft 6 1 m ladder against the roof and climb.
