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Choosing The Right Deck Drainage System (And The Mistakes To Avoid)

It’s crucial to find the right deck drainage system and be aware of the common mistakes to avoid. Read all the details here.

Choosing The Right Deck Drainage System (Mistakes To Avoid) - ACR

Having a deck installed is a great way to use your outdoor space. It allows for a relaxing space right outside your home, where you can enjoy a coffee in the morning or sunbathe in the summer. If you’re going to install a deck, you need to have a good deck drainage system installed with it.

You’ll want to avoid your decking getting waterlogged, as that will affect the wood and lifespan of it overall. That’s why you have your choice of drainage systems, that will direct water away to the ground.

Here are the options that are available to you, and the mistakes to avoid when doing so.

Pick The Right Drainage System

When it comes to decking, you have two main options: under or over joist drainage. They both have their benefits and downsides, so let’s look at them both.

Under joist drainage: These systems are designed to let water trickle through the slats on the deck, and then run away from the deck. It’s a good idea in theory, but the biggest problem is that eventually, the wood will rot from being allowed to get wet. It can also trap in moisture, which isn’t ideal. Eventually, the wood will rot and break down.

Over joist drainage: These systems are designed to catch any water before it comes into contact with the joists. It’s designed to avoid the issues of wood rot, allowing water to escape before it ever comes in contact with the wood.

These are the basics when it comes to deck drainage, but there will be more things you need to consider when installing yours.

Install At The Right Time

The best time to install a drainage system is when you’re installing the deck itself. It’s best if it’s in place right away, as that will allow it to work draining water as soon as you need it to. If you’re considering having a new deck installed, make sure that you’re budgeting to have a drainage system placed in too. It’s much harder to have one installed after the fact, and the wood in the deck will suffer water damage until you do so.

DIY Or Expert Installation?

This is the first thing you need to consider when thinking about drainage. If you’re going to have a system installed, should you call in an expert, or can you do it yourself? There’s plenty of pieces online showing you how to install drainage, but it’s usually better to have an expert do it for you.

A drainage system is a complex piece of equipment to install, even for a very experienced DIY enthusiast. While you may do a decent job of it, you really need an expert to handle it for you. After all, if anything goes wrong then the wood in your deck is going to suffer.

There’s safety to think of as well. Dealing with decking does come with certain risks, and you don’t want to compromise your safety. The experts will have installed hundreds of decking drainage systems, so they know how to do it while reducing the risk for everyone.

Finally, you’re hopefully having an expert help you with your decking installation. As they’re already doing the installation, you should be able to have them install the drainage system for you as part of that. Any good expert will recommend this to you in the process, to improve the longevity of the finished product.

Pick The Right Drainage System

There is a lot of variation between drainage systems, so you need to make sure that you’re using the right one for your deck. For example, choose a system with round or V-shaped channels, as this will allow them to still allow water through, even if debris gets knocked in.

Also, ensure that your drainage is directing water away down natural slopes in your yard. That should allow water to move away from your home, and stop it pooling. Make sure there are multiple drainage channels too, so water can run away at multiple points along the deck as well.

When choosing a drainage system, take the amount of rain and snow you get into consideration. If you get a lot of rain, you’ll need a drainage system that’s designed to handle heavier water flow. Without it, you’ll not get the same results, and there could be overflow.

Finally, find a system that will last. Getting decking drainage isn’t cheap, and it’s very tempting to pick the cheapest option to save money. However, you need something that’s good quality, to ensure that it will last for a long time. You don’t want the drainage system to fail before the deck is ready to be replaced.

Prepare Your Deck For Rainy Weather 

You should be looking to protect your deck from wet weather, and having a drainage system installed is part of that. You will need to do some other maintenance on the deck too though, to ensure that water can’t enter the wood and cause problems.

For example, you need to be regularly cleaning your deck. This most typically should be sweeping, to remove any debris. Also, check your deck to see if it’s fully sealed. Drop a few drops of water onto the wood, and see if it beads. If it soaks in instead, you’ll need to reseal the wood to make it water resistant.

If you ever see any problems with the deck, such as rotting wood, then it’s a good idea to call in the experts to correct the problem. They can replace parts of the wood to stop the spread of rot, and get it into top condition ready for wet weather.


As you can see, a good quality decking drainage system is essential. It helps keep your deck dry, and avoids rot and mold damage that comes with water. Have an expert install a good quality drainage system for you. They’ll be able to help you pick a good one that will last a long time.