How To Acclimate Hardwood Flooring

A hardwood floor is one of the most beautiful, natural features you can place in a home. It’s a timeless, durable material that can warm up a room for decades. But that beauty depends on a quality installation job.

A lot of people don’t know that a good hardwood installation begins way before you lay the first board with the acclimation process. Wood behaves almost like it’s alive (because it used to be alive when it was still in the tree), and like all living things, it needs specific conditions to thrive.

Follow this guide to learn how to acclimate hardwood flooring. We explain the danger of installing a floor WITHOUT acclimating it correctly and show you exactly how to make sure your floor stays as perfect as the day you have it installed.

Is it Important to Acclimate Hardwood Flooring?

Every hardwood flooring manufacturer will advise you to acclimate your new flooring properly. But why? Is it really that important? Yes. In fact, it’s one of the most important steps to ensuring you get the amazing, long-lasting hardwood floor you are paying for.

Proper Acclimation Will Prevent Problems Down the Road

To see why acclimating your floor is important, it’s helpful to remember where wood comes from. If you think of what you know about trees, you know that they take water from their underground roots and move it up the trunk, fighting the force of gravity, to the leaves and branches. The physical properties that allow wood to absorb and transport moisture still exist when the tree is cut down and processed into hardwood flooring.

That means that hardwood floors will suck up moisture from the subfloor or the air around them. And when a floor does that, the results can be a disaster.

Hardwood floors need to be installed in homes that have the right conditions (especially temperature and humidity). If the conditions are wrong, or if the wood planks do not have time to fully acclimate to the conditions in the room, they will expand or contract after installation.

If a hardwood floor expands or contracts too much, it will literally pull itself apart. This may not happen until months after installation when the temperature and humidity change with the seasons, and by then it will be too late. Acclimating the floor ensures that this will not happen to you.

Improper Installation Will Void the Floor’s Warranty

Like many luxury products, most hardwood floors will come with a generous manufacturer’s warranty. This will cover you if the materials themselves are defective. But to qualify for the warranty protection, you need to install the floor according to the manufacturer’s directions for that specific type of flooring.

If you don’t acclimate your new hardwood properly, it will void your warranty. If you end up having problems, you will be responsible for replacing the floor yourself.

The manufacturer’s directions will always tell you how to acclimate your flooring before installation. Make sure to know the requirements of your warranty and follow the directions carefully. Not all floor materials are the same so it’s important to follow the directions specifically for the flooring product you are buying.

If you are having your floor installed by professionals, ask them to show you that they are meeting the requirements of the warranty. You might consider saving pictures of a moisture test.

How Long Does it Take to Acclimate Hardwood Flooring?

The short answer for what to expect when acclimating hardwood flooring is several days. It might take around a week to acclimate your flooring, but it might take longer.

Start by following the installation instructions for your specific wood flooring product. This is essential to qualify for your warranty.

There are many factors that affect acclimating time, from plank size to wood type. Larger planks need longer to acclimate than small planks. Some woods, like tropical woods, are going to need longer to acclimate to most climates. If you open all of the wood packaging and place spacers between boards, the extra air exposure will speed up the process.

Since acclimating times will vary so much, you need to plan for a week but rely on a digital moisture tester to tell you when the wood is actually ready. It might take only a couple of days, but if it takes more than a week for the wood to acclimate, you must wait until it is ready.

When in the Building Process to Install Hardwood Flooring

Flooring should always be installed in a new home or large remodel as late as possible in the building process.

This is especially true for hardwood floors in order to protect the flooring from damage and to help with proper acclimation. The wood needs to acclimate to realistic living conditions in the home, which means:

  • All windows and doors should be installed
  • Wet processes like wall texture and paint should be complete and dry
  • All heating and cooling systems should be installed and operating normally for temperature and humidity in the house

How to Acclimate Hardwood Flooring 

Acclimating your hardwood floors begins with proper planning. Don’t expect to haul the planks in and start installing them right away. Plan for roughly a week between delivery to the project site and installation, depending on the specific wood you choose. If you are building a new house, schedule the flooring delivery as late as possible in the building process.

Invest in the time and tools to do things right. A simple moisture meter will allow you to be precise and confident that your wood is fully acclimated to the space.

Remember that hardwood planks were recently living trees. In some ways, hardwood still behaves like it’s alive. So treat it accordingly and keep it out of extreme temperatures and other hazardous conditions.

How to Prepare the House for a New Hardwood Floor

Hardwood floors are sensitive to moisture and temperature. To prepare your space for a new hardwood floor, you need to make sure that these conditions are appropriate for the flooring.

First, if there are any major sources of moisture in the house and air, you should isolate these well before you install a new floor. Obviously, any leaky plumbing should be corrected, but that is not all:

  • Sometimes houses are built over a crawl space that allows a lot of moisture to come out of the ground and transfer to the subfloor. A plastic tarp can isolate the ground moisture to dry the subfloor environment.
  • If your house has a basement, check to see that any sump pumps or other moisture control measures are sealed with a tight-fitting lid. Open groundwater in the basement will humidify the whole house and could lead to extreme wood expansion problems at certain seasons.

These fixes are especially important if the hardwood is going to be installed near any of these moisture sources.

If your house is sealed up from excess moisture, be sure that the temperature and humidity in the house are at normal living conditions. This means turning on the furnace or air conditioner to make a realistic humidity in the air. Even if you don’t have forced air systems, use whatever heat is in the house to set the temperature to a normal living range.

You don’t want to acclimate your wood to a house that is freezing cold or way too hot because once you move in, the hardwood will have to acclimate to a whole new temperature range and could pull apart.

How to Store Hardwood Flooring Before Installation

Throughout the acclimation process, keep your hardwood out of extreme conditions. It needs to be dry and not too hot or cold. Some variation is okay but new hardwood flooring should never be stored outdoors in the yard or in a garage that is freezing cold or very hot. At all times, keep the wood within moderate conditions (inside a building).

The best place is inside the room where the wood is going to be installed. Then the wood can acclimate to the exact conditions of the room. If that’s impossible, the nearest adjacent room will work just as well.

Once the wood arrives at the job site and you are ready to start acclimating it, there are some things you can do to make acclimating easier:

  • Open up all the wood packaging. Most wood products will be in cardboard boxes and sealed with plastic. Cut off all of the plastic and flatten the cardboard so that air can reach the stacks of boards better.
  • If you really want to try and speed the acclimating, use spacers (such as scraps of wood) in between individual boards so that the whole board is exposed to air. The greater exposed surface area should really help to speed up the process.

How to Test the Moisture Content on Hardwood Flooring

Fortunately, there are modern tools that test the moisture content of wood and display the moisture as a percentage. These moisture sensors are pretty affordable (less than $30 on Amazon) and easy to use.

To use a wood moisture meter, first see whether the instructions tell you to calibrate the sensor for the type of wood. Some sensors will have baselines for different wood types (pine, ash, etc.) and require you to calibrate them to the proper setting.

Then just insert the prongs into the underside of several wood planks to make a reading. You should test roughly 1 out of every 20 planks so you know the average moisture content across the whole supply of wood.

How to Know When The Hardwood is Properly Acclimated

Test the wood soon after delivery and record that number as a baseline. Also, test the subfloor material in several locations to see its moisture content.

Test the wood every day or two to see the changes in moisture content. The goal is for the moisture content of the floor and subfloor to be almost the same.

If the difference in moisture between the floor and the subfloor is more than 4%, the wood is not acclimated. You need to wait until the moisture content of the flooring and the subfloor come within 4% of each other.

If your hardwood planks are extra-large (wider than 3 inches) you should wait until the relative moisture content is within 2%. Good acclimation is even more important on large boards.

At all times, remember to follow the manufacturer’s recommendations for the relative moisture content and other acclimating instructions. This will ensure that you qualify for any warranty on installation and that your floor comes out looking great.