The sinister made simple: how does your timber decking “breathe”?

timber decking

We’re now right in the middle of the scary season, with Halloween right around the corner, so it’s not unusual to get a little spooked by everyday things occasionally. Your timber decking is a prime example – you might have noticed that sometimes your decking appears to be  ‘breathing’. It definitely sounds spooky and a bit like something out of a nightmare, but don’t worry – it’s completely normal! Here, we unpack a bit of the science behind it, and why your decking sometimes seems like it has a life of its own.

Is my timber decking alive?

Okay, so your timber decking isn’t alive, but you probably know that already. It is breathing, though, just not in the way that we do. The breathing is actually just changes in the wood’s water level, which causes it to expand and contract over time, a bit like a sponge.

The water is either absorbed when it rains or as water evaporates from the ground below the decking. Then, when there’s plenty of sunshine, that water evaporates. That means if there’s a lot of humidity quickly followed by hot sun, you can rapidly see your decking change in size throughout the day. Not quite as creepy as it first sounds!

Is it okay that decking breathes or should you be worried?

Unless your decking is actually coming alive (which would be terrifying!), the fact that it’s breathing isn’t a bad thing. When it’s getting beaten by the elements all day, every day, it’s expected that your wood is going to move. What you do need to worry about is something called “decking cupping”.

You can tell when your decking is starting to cup because your boards will be physically changing shape. Rather than having a flat surface, your boards will start to take on a U shape, with the middle slightly sagging. This doesn’t always happen with decking that’s breathing, but it can lead to severe damage if it does. Luckily, there are ways you can prevent it.

timber decking

How can you prevent breathing from ruining your decking?

We’ve established that breathing is normal when you have decking, but there are a few ways you can prevent it from causing damage. The first is probably the most obvious – you’ll need to make sure there’s enough space between the boards when you’re installing it. If you’re not 100% confident on the job, it can help to get some help from an expert, who will ensure there’s plenty of room for the wood to expand and shrink.

You also want to try and minimise the amount of moisture below the decking. You can do this by building your decking as high up from the ground as possible and making sure there’s proper drainage beneath the decking. If you still think there will be a problem, you can add a layer of landscape fabric to the ground to prevent the moisture from rising up.

Happily, it’s not that hard to keep  your decking in tip-top condition. You just need to know a little bit about preventing warping and cupping, and you’ll have a beautiful place to relax outdoors for many years to come. If you’re thinking of having decking installed in your garden, be sure to check out our range of timber decking kits along with our wide range of decking add-ons. You can shop online or visit our DIY stores in Wigan, Blackpool, or Preston. We’ll be happy to help with all of your decking – and household DIY – questions!