To add extensions to your downspouts, first determine where you’d like the water to drain once it exits the extended spout. The runoff destination can be a bed of gravel, garden, or another safe drainage area. Once you’ve planned the best destination for the runoff, make sure your yard is sloped at an appropriate angle to allow the downspouts to drain and disperse water without it flowing back toward your house. Then, choose the best downspouts for you and install them using the hardware provided in the extension kit.
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4 Steps to Extend Your Downspouts
Extending your downspouts can help conduct stormwater away from your house and foundation. This prevents water damage, erosion, and basement leaks. It can also prevent your garden or portions of your yard from being overwatered. There are several reasons homeowners choose to extend gutter downspouts. If you’d like to extend your downspouts, here’s how to do it.
Determine Where You Want Water to Drain
Gutter downspout extensions should be at least 4 feet long to safely direct water away from your house. But where will this water drain? During heavy rain, an excess of water can spill from your downspout, flooding an area or causing erosion. Some options for downspout endpoints are:
- Into a dry well.
- Onto a bed of gravel or stone.
- Into a garden planted with species that thrive on water
- Towards a drainage trench or drainage pipe that safely conducts water away.
Remember, an extended downspout in the wrong area can simply relocate the flooding a bit further from your home.
Correct Slope if Necessary
Most downspout extensions angle downward at a proper rate to cause water to race out, but what about the ground where the water exits? If your yard is sloped back toward your house, water coming from a downspout extension might flow back to your home. This means your downspout extension won’t work to prevent foundation damage and leaks. If your lawn is sloped toward your house, you will need to correct it with additional soil.
- Measure the slope of your yard between the downspout exit and the house.
- If the ground slopes less than 1 inch down at 5 feet distance from your home, water from a downspout extension may flow back to your house.
- Correct poor slope by adding topsoil.
- After adding topsoil, measure slope to make sure the ground falls at least 1 inch every 5 feet of distance from your house.
All homes should have a gentle slope away from the foundation. This prevents water damage and leaks. Before you install downspout extensions, make sure your yard is properly sloped to conduct roof runoff away from the foundation.
Choose your Downspouts
Downspout extensions come in several different styles. All of them can be effective. Which design you choose depends on what look you prefer and your specific drainage needs. Some popular downspout extension options are:
- Traditional aluminum downspouts.
- Flat downspouts that allow for turns and changes in direction.
- Downspouts that unroll to release water and roll back up when not in use.
- Splash blocks.
Whichever option you choose, make sure it conducts the water at least 4 feet from your home. This is essential for keeping ground near your house in the best condition and preventing leaks that can penetrate basement walls.
Install Downspout Extensions
Once you’ve chosen your downspout extension, install them according to manufacturer instructions. Each downspout extension should come with all necessary hardware. Choose a dry day and trim back any grass or bushes to make downspout installation easier.
- Install extensions while rain gutters and downspouts are relatively dry.
- Mow the grass or trim plants to make downspout access easier for installation.
- Inspect downspout piping during the next rainfall to ensure extensions are working properly.
Once your new downspout extensions are installed, check on their performance. If possible, observe them during the next rainfall to ensure there are no leaks and that water is flowing safely away from the house.
How Far Should Your Downspouts be Extended From Your House?
4 feet is the optimal distance between your house and the downspout exit. This prevents water from eroding soil around the foundation or penetrating the soil to cause basement leaks. It also keeps soil dry enough that it reduces the risk of rot and mildew to your siding. If you want to extend your downspouts, don’t bother with a product that expels water less than 48 inches from your home.
Can You Connect Two Downspouts Together?
If absolutely necessary, you can connect multiple downspout extensions together. However, additional seams mean more chances for leaks and breakages. Additionally, linking multiple downspout extensions together is more work for you. Whenever possible, seek out the proper length downspout extension for the job. This makes aluminum downspout extensions a great choice—they can be purchased at lengths of 5 feet or more.
How Can You Hide Your Downspout Extensions?
If you don’t like the look of aboveground downspout extensions or find that their presence makes lawn and garden maintenance more difficult, your best option is to install underground downspout extensions. This is a great option because it preserves the clean look of your yard and provides easy opportunities for terminating downspouts in below-ground drainage systems, such as a dry well.
You can dig a drainage trench to bury a single downspout, or you can build a drainage network that channels water from all your downspouts to a single termination point. Systems like this are efficient, long-lasting, and hidden from the eye.