How to Vent Downspouts 3 Different Ways

Underground buried downspouts move water away from your home to prevent water damage to your foundation or basement. Whether you live in the North with frigid winter freeze-ups or in the Sunbelt, where grass thrives in mild conditions, you need to be able to vent your buried downspouts.

Today, we’ll teach you how to vent your underground buried downspout system. We’ll show you how to prevent it from holding water in the wintertime so that the line doesn’t freeze up and how to move roof water from a vented cleanout.

1. Knife Cut Pipe and Popups Create a Soak Away

Designing your system to soak away water is essential for any buried downspout system. When creating a soak away, choosing the correct parts and materials is key. We like to use knife-cut pipes in our systems that connect to the pop-up. Knife-cut pipe has tiny slits that allow the water to leach into the sub-soil. We put the white sock over this pipe, so we don’t get dirt inside the line.

You also want to have a pop-up that works as a mini soak away. After your pop-up moves all the bulk water, whatever is left inside the pipe leaches away into the subsoil, as long as you put drainage fabric under that pop-up and put some stone around it. Also, any water left in a line leaves an unpleasant odor. So that’s another reason why we create soak aways using knife-cut pipe and pop-ups

Pro Tip: Connect Pipes with External Coupler

You’ll want to use an external coupler when connecting your knife-cut pipe to a solid corrugated pipe. An internal coupler will collect debris. You want an external coupler on a roof runoff system because you’ll have some roof pollution, like tree buds when they leaf out. Once you connect the lines, secure them using durable, high-quality tape.

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2. Vent Downspouts Using an Inline Catch Basin

Inline catch basins are an integral part of venting downspouts. You want an inline catch basin with a vent in case the popup ends up frozen in the wintertime. If the pop up’s frozen in the winter, you can vent your system at the inline catch basin. The vented catch basin allows water to flow out of that inline catch basin.

3. Vented Downspout Cleanout

As another measure of protection against freeze-ups, we also installed a vented downspout cleanout at the house. If there’s a sheet of ice over the popup and the inline catch basin, and you can’t get the water off the roof, it’ll come out of the vented cleanout. If you’re installing in the Sunbelt region and the grass grows over your popup and your vented inline catch basin, you can get the water off the roof at the vented cleanout.

More Downspout Tips

Another critical element to moving water away from your home and foundation is installing your system on a slope. The flatter the yard is, the more knife-cut pipe we use to take the system away from the house until the grade breaks, and we can create that slope.

As you can see above, this home had a long, flat run. We did finally make it to a break. And that’s why we stopped where we did. The grade finally broke and gave us a little drop. But we still put on a lot of knife-cut pipes. We have our vented inline catch basin if that end freezes up. In the event that we have a really odd situation where the grass grows over both, we have it vented at the house. When considering how to vent your downspout for any weather, remember that setting multiple locations for your system to vent adds an extra layer of protection to help keep those lines clear.

Want More Help with Venting Your Downspouts?

French Drain Man’s goal is to make things easy for DIYers by creating helpful how-to videos and providing a one-stop shop for all your drainage supply needs. We also offer professional downspout installation for homeowners that are done right the first time! Whether you’re a DIYer looking for tips on how to vent your downspout or a homeowner needing full-service downspout installation, French Drain Man has you covered.

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“5 stars! Excellent products and service/support. French Drain Man provided prompt answers to my DIY downspout project. The shipment came in a timely manner, which is impressive given the supply chain and shipping issues in 2022. I am a first time DIY’er and homeowner, so what felt like a huge challenge and undertaking was surprisingly made into a 2-3 day project with some simple tools and helpful youtube videos by French Drain Man. I can’t say enough great things. I plan to get a sump system and maybe even another downspout solution after we see what a heavy rain does to our property. Thank you!”

How to Vent Downspouts 3 Different Ways