Gutter down spout question (how much, roof, washer, drain)

[chucksnee]

Is there a formula for how much gutter you have as to how many down spouts you have?

I have 3 down spouts on the front of my house (2 on the ends and 1 in the middle) the one in the middle runs right into the flower bed and does nothing but dig a whole....

Do i need it? What would happen if I plugged it at the top. so water would not run out....

[Gandalara]

I wouldn't do that myself.

I'd put in a splash block or a plastic diverter hose to spread the excess around and water the flowers.

Around here, water from the sky is a blessing and I take every advantage I can think of

[harry chickpea]

Overflowing gutters are much worse than having no gutters at all. Address the problem at the bottom of the spout, using a pipe, different splash block, or other method.

[K'ledgeBldr]

General rule of thumb-
one downspout for every 20' of gutter (that 4" gutter)

The correct way is to determine the sq/ft of surface area that will require gutter.
A five inch wide by 3.5 inches deep gutter requires a 2 x 3 inch downspout every
400 square feet of roof area.

And for those gardener-types, imagine the amount of runoff created by a roof(?).
Look at a table that has estimated annual rainfall for your area and figure out how
many square foot of roof surface you have. Take these and plug them into the following
formula: Area sq. ft. X inches rain X 0.62 = Gallons of runoff per year.
That's the amount of water that could be collected in rain barrels and used to water gardens.

For inquiring minds.

[escanlan]

Originally Posted by chucksnee

Is there a formula for how much gutter you have as to how many down spouts you have?

I have 3 down spouts on the front of my house (2 on the ends and 1 in the middle) the one in the middle runs right into the flower bed and does nothing but dig a whole....

Do i need it? What would happen if I plugged it at the top. so water would not run out....

A handy little calculator for you:

Gutter Sizing Calculator - Roof Drainage Calculations

[jackbelchos]

We put diverters called "Drain Away" on our downspouts. They're very inexpensive and you can get them at any of the usual home improvement stores. They look like party blowers and have several little holes for water to spray out. When it's dry they're coiled up at the bottom of the downspout, so they're not noticeable. However, when it rains and the gutters drain, they uncoil and the water gently sprays through the holes (almost like a soaker hose). We no longer have problems with the downspouts creating holes in our landscaping.

[texdav]

I used those but they clog very easily. I now use the plastic snap together plastic drain pipe to run the water away from the house underground.Cheap easy to use and clean with a pressure washer.