Things that are not uncommon in our home. One, waffles for all major holidays. Two, a lazy napping cat. And three, a lumber pile sitting in the dining room going through the acclimation process. And that’s just what you’ll find today, a pile of framing lumber that will eventually be turned into a shelving unit for our kitchen to give it some much-needed storage. But back to the pile of wood and today’s post. Is acclimating wood for furniture building necessary? If so, how do you get the best results? And how long does it take? Let’s explore.
To preface this post, I’m not talking about hardwood floors. That’s another ballgame…well…kind of. But with hardwood flooring, I would take wood acclimation much more seriously. A new hardwood floor is not cheap and I take every precaution to ensure proper installation and follow the manufacturer’s instructions. We installed wide plank pine board flooring in our first home, and the steps we took to acclimate those boards are not the same steps we take when furniture building.
Why It’s Important To Acclimate Wood
Does wood need to acclimate? Generally speaking, wood is affected by how much moisture is in the air. It expands as it absorbs moisture during periods of high humidity levels. Then contracts during periods of low humidity levels as the moisture retreats from the wood. Wood regularly seeks equilibrium moisture content with the surrounding environment.
For example, let’s take a piece of wood that has traveled from Georgia to Vermont (geographical location matters) in the heat and humidity of the summer. There’s a lot of moisture in that piece of wood. The day we buy the piece of wood, fresh off the transport truck, we build a drawer with it in our workshop. Then bring the drawer inside and install it in our dry, over air-conditioned home. The wood is going to acclimate to the relative humidity of our home and will dry out. The wood shrinks as it dries and now there are gaps in our drawer.
While that’s a hypothetical example, this happened to us in our home. We built our kitchen island (building part one and part two) more than ten years ago, acclimating the wood before building. No shrinkage or expansion. But then we got a pellet stove, plopped it in the kitchen, and changed the interior environment. The dryness in our kitchen intensified, the moisture levels significantly dropped, and some of the island drawers started shrinking. We’ve had problems with drawers coming apart. Some have shrunk so much the drawer slides don’t work, requiring shimming.
Our home environment is typically higher humidity thanks to our perpetually damp, dirt floor basement. The introduction of a pellet stove made for a much drier environment than we normally had. We’re about to build a shelving unit for our kitchen and are currently going through the process of acclimation for the rough lumber we purchased for the project.
What Affects The Moisture Content Of Wood?
When it comes to building projects in your home, several things affect the moisture content of the wood you’re working with, which can impact the final project.
Broader based elements like your geographic location or local climate can affect the wood. Different areas have different average humidity levels. On top of that, those humidity levels change in the summer months or the time of year. For example, think about buying wood in Florida where humidity levels are more consistent vs. Massachusetts with larger humidity swings.
On a more personal level, your permanent heating system, basement characteristics, localized heating and cooling systems, and more can all affect the wood you’re working with. Hence, why it’s so important to acclimate wood in the space the finished product will go.
Is It Necessary To Acclimate Wood?
Yes, it is important to acclimate wood. Is it a required step? It’s necessary for about 95% of your projects but not always necessary.
If your project requires precision, tight joints, boards joined together, etc., best practices are to acclimate the wood. I find this is the case for almost all of our projects. After you bring the wood home from the lumber yard, take it right inside. This helps to avoid moisture-related problems with your project.
On the contrary, if your project does not require joining wood, you may get away with not acclimating the wood. I’m thinking of wood projects like open shelves where the shelf has room to expand or contract. Or maybe a live edge coffee table where the whole slab of wood is the table surface. Example of open shelf board:
How Much Acclimation Time Is Needed?
Generally speaking, as a homeowner doing DIY projects and not a fine furniture builder, a couple of weeks is a good rule of thumb for how long to acclimate wood before using it to build with. This gives enough time for the moisture content of the wood to approach equilibrium and prevent a moisture-related failure with your build.
Some people swear you can use wood the next day, and 24 hours of acclimating is good enough. I’ve even heard from folks who bring their wood inside and work with it the next morning. I’m not comfortable with that. If I’m spending the time building a furniture piece, I’ll take out a little extra insurance that the wood has adjusted to its new environment.
How To Acclimate Wood As A Homeowner?
Acclimating wood is super simple. Just bring it inside and let it sit. Preferably, put it in the room that it will go, especially if you have a home like ours where different rooms and floors have different interior climates.
One tip, don’t stack the boards right on top of each other. Use some spacers and give the boards room to breathe.
Acclimating Wood As A Fine Furniture Builder Vs DIYer
There is a difference in the quality of a fine furniture builder and a home owner or DIYer. A fine furniture builder is paid for the quality of their work, and they take extra steps to avoid improper acclimation. Some acclimate their wood for a long time, think months and years. A homeowner or DIYer does not need the same level of quality or effort for wood acclimation.
Many fine builders take rough cut lumber and give it various millings, including its final milling onsite. Between millings, they give the wood more time to acclimate. Well dried lumber will stay flat while higher moisture boards will move, sometimes warping or cupping. Time between millings shows the builder what to do to the wood before using it for their projects.
High-end builders also take all the guess work out of the wood’s moisture content. They often take a moisture measurement using a good pinless moisture meter. Depending on the type of work they do, and location, they’re looking for a certain measurement before beginning their work.
Good Luck Building!
We’ve waited about a week for the wood to dry out and will probably wait another week before working on our project. It used to be so hard to wait for wood to acclimate. All I wanted to do was dive in and go! But there are enough other things to occupy my time these days. So many projects and so little time. Happy building!
