
If you’re getting ready to install a deck, you’ll probably find that figuring out how far apart to space your boards is one of the most challenging parts of the process (see Part 1 & 2). There are a whole host of factors that come into play when making your final decision. After taking into consideration the shrinkage and expansion tendencies of the species of wood you’re using, the humidity, seasonal, and climatic factors, as well as the cut of your wood, you’ll be well on your way to a secure, lasting installation.
There are just a few more tips to keep in mind to help ensure that your project goes off without a hitch.

Remember to Communicate with Your Customer About Decking Board Spacing
Customers typically want their deck to look great and have little to no appearance of gaps between the boards all year long. You need to do your best to inform them about the reality of how the wood is going to move, so they won’t be disappointed when they notice the effects of shrinkage and expansion between boards throughout the year. Once you’ve calculated the amount of wood movement based on wood species, humidity, and temperature, you should be able to give them a pretty realistic picture of what to expect.

Give Your Wood Enough Time to Acclimate
When you get ready to install your decking boards, make sure to give them sufficient time to acclimate to their new environment before installation. This should help to cut down on movement and, hopefully, reduce checking, warping, or cupping. Ideally, you want the boards to reach equilibrium before installation begins. If possible, allow the boards a week or two to rest before installation. If you want to make your wood’s acclimation process even more effective over the long run, you could consider adding a UV inhibiting sealer to help block the sun’s harmful rays as the wood reaches equilibrium.

Consider Kiln-Dried Wood
If having only a very minimal amount of space between boards is extremely important to your customer, you could ask them to think about using high-quality kiln-dried hardwood. Kiln-dried hardwood tends to display a higher level of uniformity than other lumber. Make sure they’re well aware, however, that they can expect to see the price of the wood go up if they choose this alternative. Then the customer can determine whether or not it’s enough of a priority for them to take this extra step.
There’s no way you’ll ever be able to completely prevent the wood from moving. That’s not really a bad thing. Part of the charm of working with wood is its organic nature. Too much movement, however, can become a problem both for the deck’s overall appearance as well as by creating a safety hazard. It’s really no fun to get a toe, dog’s foot, or high-heeled shoe caught in between your decking boards! Following these steps should help your customer’s boards to stay close enough together as to not be overly noticeable or dangerous.
Proper decking board spacing can be tricky. The more informed you are, the better chance you have of getting it right.
