Moisture Problems in Wood Flooring
Moisture Problems are prevalent in Wood Flooring
This winter has been extremely cold and Middle Tennessee has experienced days with as much as 50 degree temperature swings and humidity changes. Have you noticed changes in your hardwood floors this winter? Do you find that your floors which were once smooth and free from gaps now have high/low areas and gapping? Do they creak and crack? If so, keep reading. Moisture problems in wood flooring are a homeowner’s worst nightmare. We know that water is public enemy #1 when it comes to hardwood flooring but where are the hidden moisture problems in wood flooring? Are they avoidable? What changes in hardwood flooring are normal in new construction and what should be cause for concern?
Common Moisture Problems Defined
Cupping– Cupping occurs when flooring absorbs excessive moisture on the underside causing the expansion and cupping with the edges of the floor raised. Hardwood flooring cups from gaining or losing moisture on one side faster than on the other. A cupped board’s surface will be concave with the edges higher than the center of the boards.
Crowning– Crowning or “convex cupping” occurs when flooring loses some excess moisture above the wood and shrinks on the underside and leaves the edges of strips lower than the centers. [image] Some cupping should be considered normal, especially with wide planks (5” and wider) and especially in plain-sawn boards.
Prevention – In new construction, builders should first get the house ready for the wood establishing appropriate temperature and humidity conditions in the home which will vary depending on geographic location. Hardwoods should never be installed before the HVAC system has been installed and is in operation as it is important to keep a constant temperature and relative humidity in the home. All “wet-work” or anything that emits moisture i.e. painting should be also be complete. Once the house is ready for the wood, then the wood will need to acclimate to the temperature/humidity in the house. By allowing plenty of time for the wood to acclimate, you effectively reduce the risk of moisture problems.
Another way to prevent/reduce moisture related problems is to keep the humidity levels consistent during the summer/winter seasons. You can monitor the average relative humidity in your home using an inexpensive humidistat from your local home improvement retailer. If you notice big swings in humidity, consider purchasing a whole house humidifier and humidify/dehumidify as needed.
Replacing a cupped floor is usually the worst choice of treatment. In most cases, the floor that is already in place is the best choice for a trouble free floor in the newly established environment. The treatment consists of first eliminating the source of the moisture, drying the floors. Make sure all outside drainage moves rainwater away from the home. Regrade if necessary. Make sure that there is a water vapor barrier installed and sealed. Weight it down with bricks to prevent shifting. Be sure the entire crawl space is ventilated on all walls and that the vents are open. If there are areas that are not ventilated, provide a way to circulate air through a humidistat-switched automatic fan connected to an outside vent. You could also couple the fan to the air conditioning/furnace fan.
When wood floors are installed according to NWFO best practices, consistent humidity levels are maintained in the home and with proper care/cleaning, homeowners should not have moisture problems in wood flooring. What problems have you experienced with your wood floors? Comment and let us know. We’d love to hear from you!
Source: National Wood Flooring Association