Once you have your decking boards at the job site and you’re ready to install them, it’s time to start doing what you can do to help them look their best (see Parts 1 & 2). This involves two main steps: sanding, acclimation, and cleaning. In this article, we’ll look at the first of these three steps to give you an idea of how to go about sanding your boards correctly.
Sanding Your Decking Boards Will Help Smooth the Rough Spots Out
First of all, when you get ready to sand your decking boards, take note of the grain direction. When you go with the grain instead of against the grain, you’ll see better results. Think of it as sort of like when you rub an animal’s fur. If you rub it in the right direction, your pet is happy. If you rub their fur in the wrong direction, they often react by jumping up and running away. Though your wood won’t run off on you if you sand against the grain, it won’t perform as well.
So what exactly happens if you fail to sand your wood correctly? You can end up with rough spots. As hard as you try, however, you may end up creating some rough spots where the wood will tear out. This is because the grain of the wood can be unpredictable. You’ll notice changes in the grain are especially common around knots. When your boards first arrive, they’ll likely have rough spots around the knots that you see in the wood. Perhaps you don’t see any knots on a particular board. You should still check it for rough spots, because it may have been sawn next to another part of the tree where there was a knot. This could still be enough to change the grain pattern and make a rough spot. Check your boards over, look for the rough spots, and give them extra attention when you sand your boards.
Maybe your shipment of decking boards includes vertical boards. These boards can also contain rough spots. They’re sawn at almost 90-degree angles to the tree’s growth rings on their wide face. It’s very difficult to predict the grain direction in boards like these. They also have tough fibers that can create hard little ridges that stick up higher than the rest of the surface. These ridges can be uncomfortable if people walk on your deck barefoot. Ipe and Cumaru are known for these ridges, so be aware of them and work to sand them down.
Perhaps you’re wondering why the lumber yard doesn’t take care of these rough spots before the boards arrive at your job site. They don’t want to run the boards through their drum sander, because there’s no reason to waste as much of the valuable wood that a sander would typically remove. Only the rough spots and raised ridges need to realistically be removed. Those aren’t going to be on the majority of your boards’ surfaces. So it is best to take care of them yourself after you install your boards. You can use a random orbital sander or handheld belt sander.
In our fourth article in this series, we’ll look at another step involved in finishing your decking boards.