After you’ve considered the installation method and location of your deck (see Part 1), you’ll be well on your way to discerning a reasonable acclimation time period for your decking lumber. After considering two more factors, you’ll be even closer to arriving at a specific timeframe for the task.
What’s the Weather Like?
No, we’re just not trying to make small talk, here. The climate and current season make a major impact on how much time your decking lumber will need to come to an equilibrium with its environment. Throughout the winter months, lumber tends to remain fairly stable along with moisture levels. Sure, the afternoon sun may certainly cause the temperature to rise, but since the temperatures are cooler and there is less moisture in the air, the impact will be negligible In addition, transportation from lumber yard to job site probably won’t make a major impact on the lumber.
As a result, you really don’t need to allow for acclimation during the colder months. Maybe give it a day, stacked and covered, prior to installation, but really, that’s all you’ll need — regardless of installation method. (Of course, you should be cautious about gap spacing, realizing that whatever size gap you use will be greatly reduced when moisture levels increase.)
Is Your Decking Lumber Pre-Finished?
Of course, no decking lumber is actually a finished product until after it’s properly installed; however, pre-finished decking will behave differently than unfinished boards. Even if the boards are finished, they won’t be sealed in a way that prevents moving (many people misunderstand the term “sealer” or “sealant”). While finish can slow wood movement, it cannot prevent it. What a finish will do, though, is add moisture to a board. So if you’re using pre-finished boards, you need to consider how long it’s been since that added moisture had been added; it may require added time to acclimate, as a result. Now, once the boards have had time to acclimate, the finish will be beneficial by keeping them more stable.
What’s Your Hurry?
I know, I know; we all have schedules to keep. But if there’s any question at all, it’s always best to allow extra time for acclimation. By allowing enough wiggle room in your project timeline to keep your decking lumber stacked and covered for a full 2 weeks, you’ll pretty much be safe. In the end, it’s always best to allow for a little extra time than to have a compromised deck and unhappy customer to deal with down the road.
Before we conclude this important issue, please keep in mind that we’ve been discussing decking lumber, here; the same advice would not ring true for other applications. Interior projects or any with interlocking joinery can actually become problematic if you let the boards sit around for weeks on end. But as long as you’re applying your new-found knowledge in the way that it’s intended, you really can’t go wrong.
J. Gibson McIlvain Company
As an active supporter of sustainable lumber practices, the J. Gibson McIlvain Company (mcilvain.com) is one of the largest U.S. importers of exotic woods and has provided fine lumber for notable projects throughout the world, including the White House, Capitol building, Supreme Court, and the Smithsonian museums. For more information on J. Gibson McIlvain’s lumber products and services, call Monday-Friday toll free (800) 638-9100 to speak with one of their representatives.