You should have enough gutter downspouts to effectively handle the size of your entire gutter system.
Roof gutter standard gutter dimensions.
There are two most common type of residential gutters that we will talk about in this post for reliable roof gutter sizing.
However too large a gutter downspout can look unattractive.
5 inch 5 520 square feet.
If rafter ends or fascia boards are repaired or replaced the certification shall also include the rafter end and fascia board material size type and mounting method.
The sizes available in this style are 3 4 5 and 6.
6 inch 3 840 square feet.
For most homes this will be a large enough gutter to handle the amount of water washing off of the roof but if you live in a particularly rainy area you will want to opt for wider downspouts to be installed with your new gutters.
6 inch 7 960 square feet.
Get 7 or 8 inch gutters.
5 inch 2 500 square feet.
Contractor certification certifying the roof gutter and downspout type sizes gage roof gutter slope and mounting method.
Houses with big steep roofs however may need wider gutters and extra downspouts to keep rainwater from overflowing.
5 inch standard k style gutter shop 5 gutterbrush.
The larger a gutter downspout the more water it can drain quickly.
7 and greater are appropriate for churches and larger commercial buildings.
This is most common in the k style gutters.
Half round adjusted square footage of roof.
This type of down spout is considered the standard downspout style in households and is used with a 5 k style guttering system.
They ll cost more and probably require a custom order through a professional installer.
Measure your gutter across the top from the back where the gutter meets the home to the outer edge.
It also comes in sizes 2 3 and 3 4.
Five inch k style gutters.
If a roof s various drainage areas call for different size gutters go for the biggest one k style.
When you are considering what kind of gutters to get keep in mind that different gutter shapes have a significant impact on the capacity of the gutter.
K style sizes will typically range from 5 to 6.
See photos below most residential gutters will measure approximately 5 inches across the top with the actual opening being approximately 4 5 inches.
Increase the pitch of the gutter.
The standard is about inch per 10 feet.
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.
These two types are able to handle the rainfall on majority of homes statewide.
Gutters for proper roof gutter sizing.
Then use the chart below to see what size gutter you need.
There are two main common sizes of gutters and one of them is 5 inch.
Multiply the drainage area by the roof pitch factor and rainfall intensity to find out the adjusted square footage.
