Do the planks of your wood floors bulge upwards? If so, you might have a case of buckling hardwood floors, just like laminate floor buckling.
Wood is hygroscopic, meaning it gains or loses water as the moisture content of the surrounding air changes. A change in humidity means a change in moisture content that causes wood to expand or shrink. When it expands without having a sufficient expansion gap, it buckles.
Here’s how it looks.
But that’s not the only cause of hardwood floor buckling; I’ve listed more than 5 reasons for buckling.
You might have spent thousands of dollars, time, and sweat installing wood flooring. Now, if the hardwood starts buckling, it may attract additional money to repair. Repairing wood floor buckling typically costs $3-$8 per sq ft., according to fixr.com. I’ll also share buckling prevention tips at the bottom of this article to save you from that.
Before we get into the fixes, let’s find out what causes buckling in hardwood floors.
There are many causes of a buckled hardwood floor. They can occur due to incorrect installations or moisture.
Increase in Moisture Condition
One of the leading causes of buckled hardwood floors is the change in humidity. Hardwood floors will expand or contract due to the surrounding atmosphere’s moisture content. When the wood expands, If there’s no expansion gap, the wood plank will collide with the wall, and as it can’t push the wall further, it buckles.
As I already told you above, hardwood absorbs water. There are only two ways wood will get water — either from the moisture from the air or direct water contact.
I’ll discuss moisture in this section and water damage in the next section.
How does moisture affect hardwood?
The acceptable moisture level for hardwood indoors is from 6-9%. Humidity levels above 50% can cause the wood floors to swell and hence buckle. Therefore, interior surrounding air humidity is good to be between 30 and 50%.
I’ve seen many websites mentioning moisture, humidity, and temperature as separate causes for buckling. Let me tell you, all of the reasons are correlated. Moisture, humidity, and temperature are proportional to each other. Hence I’ve not written the same causes separately because it doesn’t make sense.
Also, I shared a chart above which provides the relation between these 3 things.
Now, let’s find out what are the potential sources that increase surrounding air moisture content.
- Faulty HVAC systems
- Change in weather.
- Non-breathable rugs on the hardwood flooring
- No acclimation
Sunlight through windows can generate heat and fluctuate the room’s humidity level due to the greenhouse effect. If there’s a fault in your HVAC system, then it can’t control the room humidity level. Therefore, buckling can happen.
Weather changes can result in relative humidity changes in the surrounding air. If your HVAC is inefficient, humidity fluctuation can buckle the hardwood floor.
If you put rugs on the hardwood flooring, make sure they are breathable. Otherwise, the rug can trap moisture between the rug and the hardwood floor. Avoid latex-backed rugs.
If you don’t acclimate the hardwood floors, they can swell when exposed to the air during installation. Properly acclimated wood floor achieves equilibrium where it no longer expands.
Another source of moisture is direct water contact. Any standing water on the hardwood floor should be avoided, or the wood will start absorbing the water through its pores which causes warping and discoloration. That can also cause buckling between two hardwood planks.
It is essential to wipe away water immediately after an accidental spill. The first 24 hours of contact between water and wood is crucial and must be acted upon quickly.
One of the early signs of water damage on the wood is when your plank has turned black or has dark staining. If any of your planks have those signs, you will have to dry them and wipe the excess moisture off with disinfectant and a cloth.
- Incorrect subfloor construction, such as wet subfloor
- Poor drainage system
- Water from appliances/leaks
- Wet/ steam mopping
While moisture is the only cause of wood swelling, a proper installation can prevent them from buckling. Incorrect installation means many be anything like incorrect glue, improper nailing, etc.
Improper Installation Methods.
- No Expansion Gap
- Poor Subfloor Preparation
- Improper nailing
- Poor adhesive
As hardwood floors shrink and expand due to moisture, you must keep an expansion gap between the wood planks and the wall. That means wood planks will get enough space to expand and won’t push the wall. Otherwise, wood planks will try to push the wall without having enough expansion space, pushing each other and buckle.
Moisture can migrate from the subfloor to the hardwood planks. To stop this, you must install an underlayment/moisture barrier between the wood floor and the subfloor, such as concrete.
Finally, nailing and putting adhesive incorrectly can buckle the hardwood flooring.
We know what causes the buckling of hardwood floors, but are there any fixes for it? That will depend entirely on the individual situation of the buckled hardwood floors.
If the hardwood boards have just started to buckle, it may be easy to reverse the buckling without replacing the planks. But if the planks have buckled and gotten damaged, the only fix is replacing the hardwood boards.
As we currently know, there are only two methods to fix buckled wood floors; using a dehumidifier and replacing the planks.
Before fixing the buckled wood floors, it’s essential to fix the issues that dampen them. For example, stop the water from buildings and plumbing leaks or water leaking from dishwashers, refrigerators, or appliances.
This will solve half of your problems.
Additionally, check if the moisture is leaking from the subfloor. In that case, you may have to reinstall the hardwood boards of the entire floor by putting a moisture barrier in between. After this, there are negligible chances that the hardwood will attract any moisture.
Here’s an image taken while I was repairing a water leak that caused damage to the hardwood floorings.
Not fixing these issues will cause wood floors to swell and buckle again.
If you have an area on your wood flooring with minor buckling, you can fix it quickly with the help of an electric fan and a dehumidifier.
When your hardwood floors buckle or have started the process of buckling, you will find a lot of excess moisture in that area. Use a towel to soak up all the excess water in that area correctly.
This step is important as excess moisture can stay trapped between the hardwood floor’s dirt and debris, which can buckle in the future.
Dry the area with towels and start vacuuming the minor buckled area thoroughly.
To speed up the drying process, use an electric fan after you have toweled out all the moisture.
Once the drying process has started, leave a dehumidifier on for a minimum of 24 hours. That would cause the boards to return to normal if the buckling was minor, as we initially thought.
I got this dehumidifier from Hysure which is pretty good.
If the boards still show signs of buckling despite dehumidifying them, replacing them is the only option.
Replace Damaged Boards
Planks or boards that have buckled up will require replacing.
- Replacement planks – you may have these from the installation
- Pry bar
There are many different ways to replace hardwood planks. The provided method does not require cutting or the use of many tools.
Remove the Molding
The molding or the baseboard is on the bottom corners of the room. To access the hardwood planks, you will have to remove them.
Most moldings are glued to the wall with adhesives, while the modern ones may have a locking system. Figure out your molding, though removing both types of molding requires the same method.
Use a prybar on the molding and pull a part of it off. This will forcibly remove the adhesive and make it easier for you to pull off the rest of the molding.
Remember to label or keep the moldings around the position you pulled them off from so it will become easier to put them back in their place with no confusion.
Replace damaged boards
Like laminated floors, you need to manually remove the buckled or peaked boards and replace them with new ones.
Check this video for instructions.
Make sure that you are leaving enough space for the new planks to expand in temperature. It will also be beneficial for you to disinfect the buckled area and wipe away all the moisture before installing hardwood flooring.
Put back the molding.
When you have done everything, put the molding back in its place.
You can also use an adhesive between the wall and the molding to put it on better.
Now that you know how to replace the boards, let’s learn some preventive methods to avoid buckling.
How to Prevent Buckling
Keep Expansion Gap
When installing a hardwood floor, other than letting it acclimate, you also have to make sure you leave enough gaps between the hardwood floors, giving them enough space to expand if needed.
Not giving the planks enough space to expand will end up causing buckled planks.
Acclimate Hardwood Planks
When you install a hardwood floor in your house, you have to let the hardwood floors acclimate to the condition of the environment. That is because hardwood floors can expand or contract due to the temperature.
Acclimation means the hardwood has reached its equilibrium moisture content (EMC), which neither expands nor contracts further.
Wood floors with little time to acclimate to the environment will end up buckled.
Keep Wood Flooring and Water Contact as Minimum as Possible
Whenever you spill a liquid on the hardwood floor, be sure to wipe it up as soon as possible and dry it afterward. That will prevent moisture from building up and also keep the hardwood floor safe from water and moisture damage.
One of the surefire ways to avoid buckling is to get your hardwood flooring checked for leaks regularly. If you suspect that the hardwood flooring is showing signs of buckling, check around for possible leaks.