Water pooling on wooden deck

[DarkKnight]

Hi all!

What's the best way to prevent water pooling on a wooden deck that sits in a shaded area and takes a long time to dry? I'm considering adding a slight slope or possibly installing some kind of drainage system but not sure which approach is most effective without compromising the deck's structure. Any tips or recommendations? Thank you in advance!

[FatimaandAhmed]

Hi! I totally get the frustration with water pooling on a shaded deck. It can really mess with the wood over time. Adding a slight slope could definitely help, as it would direct water away from the surface. You’d want to be careful though, as altering the slope might require adjusting the deck’s framing, which could be a bigger project than you’re hoping for.

As for a drainage system, installing drains underneath the deck could help, especially if it’s built off the ground. If that’s something you’re considering, it’s important to make sure the drainage system won’t cause water to pool anywhere else on the property.

A simple solution could also be using a deck cleaner or sealant to help water bead off the surface. What kind of wood is the deck made of? Some materials hold up better to moisture than others, so that could affect the type of solution you go with.

Let me know if you need more details on any of these options!

[DarkKnight]

Adding a slight slope sounds promising! How much of a slope would you recommend to effectively direct water without it being noticeable? Also, for the drainage system idea, how would you go about installing it under the deck? Would it involve cutting through the deck boards or just setting something up underneath?

[FatimaandAhmed]

A slight slope of about 1/8 inch per foot should work well to direct water off the deck without it being noticeable. It’s subtle enough that you won’t feel the incline, but it’s effective for drainage.

For the drainage system, you can usually set something up underneath the deck without cutting through the boards. One popular method is to install a deck drainage system, which involves attaching panels or a membrane to the underside of the joists to catch water and direct it toward a gutter or a drain. This keeps the area below the deck dry and avoids major structural changes. If you’d prefer a DIY approach, you could use corrugated plastic or a similar material to create a slight slope between the joists and direct water to one side. Let me know if you'd like tips on setting it up!

[DarkKnight]

Thanks for the tips! That slope sounds perfect, barely noticeable but practical. Just wondering, when you’re adding the slope, how do you make sure it’s consistent across the whole deck? Any tricks to keep it even without overthinking it?

[FatimaandAhmed]

Start by figuring out where the high and low points should be. Typically, the slope goes away from the house to guide water off the deck. Mark those points on the deck’s frame or joists, then snap a chalk line between them to create a visible guide.

As you work, use a level to make sure the slope stays even. A gentle drop of about 1/8 to 1/4 inch per foot is ideal, it’s enough to let water drain without being noticeable. If you're retrofitting, you can use shims to tilt the deck boards slightly. Lay them under the boards as needed, following your chalk line as a reference. Recheck with the level every few feet to keep everything consistent, but don’t stress over tiny imperfections. The key is ensuring water flows off instead of pooling.

[DarkKnight]

Thanks for the guidance! One concern I have is how to handle areas where the slope might be more noticeable due to the deck's layout. What do you recommend if there are spots where the slope is uneven because of the framing?

[FatimaandAhmed]

If there are areas where the slope is more noticeable due to uneven framing, you’ll want to address those spots to ensure water flows off the deck without causing issues. One option is to adjust the framing by adding shims or planing down the high spots in the joists. This can help make the slope more even without having to rebuild the whole frame. If the uneven areas are minor, simply adding shims under the decking boards can also make a big difference in evening out the slope.

For larger framing issues, you might need to get a bit more involved, but it could be worth it to prevent pooling in the long run. When working with uneven framing, it’s important to check with a level as you go to ensure the water flows consistently in the right direction. If the framing adjustments are too complex, you could also focus on drainage systems like installing a membrane or panels beneath the deck to help guide the water off, even if the slope isn’t perfect. It’s all about finding a balance that works for your deck’s specific layout without compromising the structure.

[DarkKnight]

Thanks for explaining everything.