Measure the length of each gutter run.
Calculate rain gutter size.
Box gutter with rain water head at end of box gutter.
6 inch 7 960 square feet.
Measuring existing gutters 1.
If a roof s various drainage areas call for different size gutters go for the biggest one k style.
Simplified suitable for flattish roofs with little or no vertical faces or steep roofs draining to one side of box gutter only or any roof if you are in a hurry and make the necessary allowances for all catchments.
To limit the effects of thermal expansion in gutters 50 ft.
The steeper a roof s pitch the more windblown rain it can collect.
15 m is a practical maximum gutter length to be served by a downspout.
Measure the height of.
Find the rainfall intensity for your locale.
Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted square footage.
5 inch 5 520 square feet.
The saf perimeter systems gutter downspout capacity table click to enlarge relates downspout size to gutter sizes.
5 inch standard k style gutter shop 5 gutterbrush.
Calculations are based on level gutter capacity as experimentally determined by the national institute of standards and technology nist.
Then use the chart below to see what size gutter you need.
Now architects engineers designers and contractors can easily and accurately size downspouts and gutters according to the specifications in smacna s architectural sheet metal manual 7th edition 2012.
Adjusting for pitch and rainfall.
The downspout and gutter sizing calculator is located on the tools cad and apps page of the smacna website.
Run the tape measure from 1 corner of the gutter as far as you can go toward.
Rainfall intensity is measured in a 5 minute interval translated.
Downspout sizes must not exceed the bottom width of the gutter.
Multiply length peak to.
How do you calculate gutter size.
See photos below most residential gutters will measure approximately 5 inches across the top with the actual opening being approximately 4 5 inches.
5m x 4m x 4 2 40 square metres.
Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted.
How to calculate gutter and downspout capacity step 1.
Measure the roof to get the watershed area the area from which water will run off.
Find the width of the gutters.
Measure your gutter across the top from the back where the gutter meets the home to the outer edge.
Place a sturdy 20 ft 6 1 m ladder on 1 side of your house so that you can reach.
