Author: Vasi Popovici
When the summer sun finally breaks through the clouds and the rainy season takes a break, Portland homeowners start tackling their home improvement lists. While painting the exterior or landscaping the yard are common choices, summer is actually the best window of the year for installing new hardwood floors. Timing is everything when it comes to wood, and our warm, dry months offer the perfect conditions for a flawless installation.
Wood is a natural, living material that reacts to its environment. In our region, the weather swings from damp, cold winters to hot, dry summers. Understanding how these seasonal shifts affect hardwood will help you plan your project for the best results:
- Damp Winters: Wood absorbs moisture and expands.
- Dry Summers: Wood releases moisture and contracts.
Here is why local homeowners should consider scheduling their hardwood floor installation during the summer months, along with the science behind wood behavior and practical tips for a successful project.
The Relationship Between Wood and Humidity
To understand why summer is the prime season for hardwood flooring, you have to look at how wood interacts with moisture. Wood behaves like a sponge. When the air is damp, wood absorbs moisture and expands. When the air is dry, wood releases moisture and contracts.
In Portland, our winters are notoriously wet. The outdoor relative humidity can stay above 80% or 90% for months on end. Even inside a heated home, the air can fluctuate wildly depending on your heating system. When we install wood during these damp months, the subfloor and the new flooring material are often holding onto higher levels of moisture.
In contrast, our summers are warm and dry. The indoor and outdoor relative humidity drops to a much more stable range, typically between 30% and 50%. This is the target humidity range for residential homes. By installing your hardwood floors when the ambient moisture is already in this sweet spot, you minimize the risk of drastic wood movement later in the year.
- High Moisture Installation: Shrinks in dry summer, leaving gaps.
- Low Moisture Installation: Expands in winter, causing boards to cup.
- Summer Installation: Starts the wood at a balanced midpoint for gentle adaptation.
Acclimation: The Secret to Long-Lasting Floors
Before a single board is nailed down, the flooring must undergo a process called acclimation. This means letting the hardwood sit inside your home to adjust to the temperature and humidity of the living space. Acclimation is not just a recommendation; it is a critical step that dictates the long-term stability of your floors.
During the rainy winter months, acclimating wood can take a long time and require careful monitoring. If the delivery truck drives through a downpour, the wood can absorb moisture during transit. Once inside, it takes longer for that excess moisture to evaporate, especially if your heating system is drying out the air unevenly.
Summer makes acclimation much simpler and faster. The dry, warm air allows the wood to reach its equilibrium moisture content (EMC) quickly and evenly. Instead of fighting damp conditions, the wood adapts to the home's natural summer state.
For most standard solid hardwood products, we recommend letting the wood acclimate in the room where it will be installed for at least three to five days. During this time, the boards should be cross-stacked (stacked in a log-cabin style) to allow air to circulate around all sides of the wood. In the summer, this process is highly predictable, giving us confidence that the wood is ready for installation.
Curing and Drying Times for Wood Finishes
Once the hardwood is installed, it needs to be finished (unless you chose pre-finished planks). The choice of finish and how it cures are major factors in your project's timeline and quality.
There are two primary types of polyurethane finishes used today: water-based and oil-modified. Both are excellent options, but they dry and cure differently depending on the weather.
Water-Based Finishes
Water-based finishes, like Bona Traffic HD, have become the standard for modern homes. They dry quickly, have very low odor, and do not yellow over time, keeping the natural look of the wood. These finishes dry through evaporation—the water in the finish must escape into the air for the protective resins to harden.
Warm summer air and lower humidity levels speed up this evaporation process. On a typical July day in Portland, a coat of water-based finish can dry enough for light foot traffic in just a few hours. This allows us to apply multiple coats in a single day, shortening the overall project timeline and getting you back into your home faster.
Oil-Modified Finishes
Oil-modified polyurethane is a traditional option that provides a rich, amber glow and deep protection. Unlike water-based options, oil finishes cure through a chemical reaction with oxygen in the air, a process known as cross-linking.
This chemical reaction requires warmth and fresh air. Cold, damp winter air slows this process down significantly. In the winter, a single coat of oil poly can take 24 to 48 hours to dry, extending the project by days. In the summer, the warmer temperatures accelerate the chemical reaction, allowing the oil finish to dry and cure in a fraction of the time.
Faster drying times mean less opportunity for dust, pet hair, or insects to settle into the wet finish. The cleaner the environment during the drying process, the smoother and more perfect the final surface will be.
The Practical Advantage of Summer Ventilation
Refinishing and installing hardwood floors can create dust and odors, even with modern dust-containment systems. Proper ventilation is essential for safety, air quality, and finish curing.
In the middle of January, opening your windows to vent fumes is a tough sell. Doing so lets in freezing, damp air that can chill the subfloor and ruin the finish application. Cold air holds less moisture, but cold surfaces can cause finishes to cure improperly, leading to a cloudy or soft finish.
Summer allows for easy, natural ventilation. We can open windows and use fans to pull fresh air through the house and push dust and fumes outside. This keeps your home's air cleaner and helps the finish dry under optimal conditions. It also makes the process much more comfortable for you and your family if you decide to stay in the home during the project.
Additionally, if we are working on a project that involves sanding, the ability to keep windows open helps clear any residual airborne dust quickly. While we use advanced dust-extraction systems that capture 99% of the dust, having a fresh summer breeze helps clear out the rest.
Managing Your HVAC System During a Summer Installation
While summer offers the best natural conditions, you still need to manage your home's indoor climate. A common mistake is turning off the air conditioning during installation to "let the wood breathe" or, conversely, blasting the AC to stay cool.
The goal is to keep your home at its normal, year-round living conditions. If you typically keep your thermostat at 72°F, you should maintain that temperature during acclimation, installation, and curing.
Here are a few guidelines for managing your HVAC system during a summer flooring project:
- Avoid Extreme Temperatures: Do not let the house get too hot or too cold. Keep the temperature between 60°F and 80°F.
- Control Humidity: If you have a central air conditioning system or a heat pump, keep it running. Air conditioners naturally dehumidify the air, helping to keep the indoor relative humidity in the ideal 30% to 50% range.
- Minimize Air Currents During Curing: While ventilation is good for clearing fumes, avoid having strong drafts blowing directly across the floor while the finish is wet. Turn off ceiling fans and close vents in the immediate work area while the topcoat is being applied to prevent ripples in the finish.
- Change Your Filters: After the sanding and installation are complete, change your furnace or AC filters. Even with dust containment, fine particles can find their way into your return vents.
Scheduling Your Summer Flooring Project
Because summer is the ideal season for hardwood flooring, it is also the busiest time of year for professional contractors. Planning ahead is crucial to secure your preferred dates.
If you are planning other renovations, like painting or remodeling the kitchen, the floors should generally be the last step. Installing new floors before painting can lead to paint spills or scratches from ladders. By scheduling your flooring project for late summer, you can complete other home updates during the spring and early summer, finishing the season with beautiful, brand-new floors.
Summer is also a great time to schedule this work because families are often away on vacation. Since installing and refinishing floors requires you to stay off the wood for a few days, coordinating the project with a family trip is a smart way to avoid disruption. You can head out to the Oregon Coast or Central Oregon for a week and return to a transformed home.
Ready to Start Your Project?
Choosing the right season for your flooring installation makes a significant difference in the final look and durability of your floors. Portland's summer months offer the perfect balance of low humidity, warm temperatures, and easy ventilation to ensure your hardwood project is a success.
At Floors PDX, we have years of experience navigating the local climate and helping homeowners select the best wood species and finishes for their spaces. Whether you want to install classic oak, modern maple, or refinish your existing floors, we are here to help.
Get a Free Quote today to discuss your project, check our summer availability, and get expert advice on the best flooring options for your Portland home. We will walk you through the options and make sure your new floors are installed to last a lifetime.