18 Sep Why Hardwood Floors Cup and How to Prevent It
Do you own hardwood floors, or plan on having them installed in your home in the future? If so, you need to learn about cupping.
What is cupping? Cupping is something that happens when a wood floor bends. The edges of a board become higher than the center and form a concave surface.
What is the main reason for cupping? Wood flooring naturally expands in warm, humid conditions and contracts during dry conditions. Hardwood floors cup when they absorb excess moisture.
What are the sources of moisture? Moisture can be present for many reasons. It can be present as a result of high humidity, flooding, and leaks from windows, doors, roofs, and plumbing.
Where are the high-risk areas in your home? Kitchens, bathrooms, basements, crawlspaces, decks, and patios are the most susceptible to excess moisture.
How can you prevent cupping? The best way to prevent your floor from cupping is to find the moisture source and remove it. This means controlling humidity levels, locating and fixing leaks, and removing liquids from floors immediately after spills.
Control and monitor air humidity levels during the dry season by installing a humidifier in the furnace or running a portable humidifier during the winter. During the summer, run your air conditioner or dehumidifier. A humidity meter will allow you to monitor and control humidity levels in your home throughout the seasons. It is best to keep humidity levels in the 40-60% range.
Proper maintenance of your wood floors can also help to prevent cupping. Clean your wood floors according to the manufacturer’s instructions. You can also check with your wood floor installer/retailer if you are unsure about the proper care of your wood floor.
How do you fix a floor that has cupping? Remove the excess moisture as soon as possible. Use dehumidifiers and fans to dry the hardwood. Mild to moderate cupping will eventually flatten out as the water evaporates and the boards stop expanding. Dry the floor as much as possible before lightly sanding. After sanding, continue to dry the wood. Screw downs boards that have loosened and fill any cracks. Floorboards that have experienced severe cupping and buckling (separation between the floor boards and the subfloor) may need to be replaced.