5 inch standard k style gutter shop 5 gutterbrush.
Calculate rain gutter size.
Adjusting for pitch and rainfall.
The saf perimeter systems gutter downspout capacity table click to enlarge relates downspout size to gutter sizes.
Measure the length of each gutter run.
Run the tape measure from 1 corner of the gutter as far as you can go toward.
Find the rainfall intensity for your locale.
How do you calculate gutter size.
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.
Water capacity values of a gutter downspout system is calculated using the height head of water a gutter can hold the outlet orifice size of the downspout and the quantity of downspouts used.
15 m is a practical maximum gutter length to be served by a downspout.
Rainfall intensity is measured in a 5 minute interval translated.
6 inch 7 960 square feet.
How to calculate gutter and downspout capacity step 1.
If a roof s various drainage areas call for different size gutters go for the biggest one k style.
Measure the roof to get the watershed area the area from which water will run off.
Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted square footage.
Measure your gutter across the top from the back where the gutter meets the home to the outer edge.
Measuring existing gutters 1.
The downspout and gutter sizing calculator is located on the tools cad and apps page of the smacna website.
Find the width of the gutters.
Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted.
5 inch 5 520 square feet.
To limit the effects of thermal expansion in gutters 50 ft.
Box gutter with rain water head at end of box gutter.
In response smacna s technical resources department has created a free downspout and gutter sizing calculator.
Place a sturdy 20 ft 6 1 m ladder on 1 side of your house so that you can reach.
Measure the height of.
5m x 4m x 4 2 40 square metres.
Calculations are based on level gutter capacity as experimentally determined by the national institute of standards and technology nist.
The steeper a roof s pitch the more windblown rain it can collect.
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.
Then use the chart below to see what size gutter you need.
Multiply length peak to.
