If you're planning to sand the surface of your decking, you might be tempted to use a square sanding machine to get the job done quickly and efficiently. However, using a square sanding machine on decking can be a bad idea, and it's important to understand why before you start.

A few days ago, we had a call from a client whose decking had been damaged. He didn’t understand why on past projects our decking was perfect, and on another one there were cracks in the decking. After a short discussion, we found out why. The contractor had used a square sanding machine. That’s why, in this article, we'll explain why using a square sanding machine on decking can lead to problems, and we'll offer some alternative methods that are better suited to the task.

Why is it a bad idea to sand decking with a square sanding machine?

There are several reasons why using a square sanding machine on decking can be a bad idea. Here are some of the main issues you might encounter:

• Uneven Sanding: Decking often has a curved or uneven surface, which can make it difficult to sand evenly with a square sanding machine. The machine is designed to sand flat surfaces, and it might not be able to adapt to the contours of the decking. As a result, you might end up with some areas being sanded too much, while others are not sanded enough. This can result in an uneven finish, and it can make the surface of the decking look patchy.

• Damage to the Surface: The high speed and pressure of a square sanding machine can be too much for the delicate surface of decking. The machine can create deep gouges in the wood or even splinter it, which can weaken the decking and make it more prone to further damage. This can also create an unsightly appearance that is hard to repair.

• Difficulty in Maneuvering: Using a square sanding machine on decking can be difficult to maneuver. The weight and size of the machine can make it hard to control and move around, especially on a surface that is not completely flat. This can result in an uneven finish, and it can make the sanding process take longer than it needs to.
  
  

What alternatives can you use to sand decking?

If you want to avoid the problems associated with using a square sanding machine on decking, there are several alternative methods you can use. Here are some options to consider:

• Hand-Held Sanding Tool: A hand-held sanding tool, such as a belt sander or orbital sander, is a great alternative to a square sanding machine. These tools are lightweight and easy to maneuver, making them ideal for sanding decking. They are also designed to be used on curved or uneven surfaces, which means you can achieve a more even finish without damaging the wood.
  When using a hand-held sanding tool, it's important to start with a coarse grit sandpaper and work your way up to a finer grit. This will help you remove any rough spots or imperfections in the wood, while also smoothing out the surface.

• Power Washer: Another option for preparing your decking for refinishing is to use a power washer. This is a great method for removing dirt, grime, and other debris from the surface of the wood. It can also help to remove any old finish or paint that might be on the decking.
  When using a power washer, it's important to use a low-pressure setting and hold the nozzle at least 12 inches away from the wood. This will help to avoid damaging the surface of the decking.

• Chemical Stripper: If you need to remove an old finish or paint from your decking, you can use a chemical stripper. This is a liquid solution that you apply to the surface of the wood and then allow to sit for a period of time. The solution will dissolve the old finish or paint, making it very ugly.
  

A few last words of advice.

In conclusion, using a square sanding machine to sand decking can be a bad idea for several reasons, including uneven sanding, damage to the surface of the wood, and difficulty in manoeuvring the machine. However, there are several alternative methods you can use to sand your decking, including hand-held sanding tools, power washers, and chemical strippers.

Professional deck sanding by our installation partner EcoSmart

When choosing a method to sand your decking, it's important to consider the condition of the wood and the type of finish you want to achieve. If you're unsure which method is best for your decking, you can consult with a professional or do some research to find the best approach.

By taking the time to properly sand and prepare your decking, you can achieve a beautiful, long-lasting finish that will protect your wood from the elements and enhance the overall appearance of your outdoor space.