A Logs End social media follower recently asked: What is hardwood floor cupping? 

hardwood floor cuppingThe following image from Wikipedia is a perfect illustration of cupping.

Hardwood floor cupping (or a wood cup) is a warp across the face width of a plank, in which the edges are higher or lower than the centre of the wood.  Some hardwood floor owners may describe this phenomenon as a “washboard” or “waves”.  It is commonly caused by moisture, humidity, improper cleaning or a water spill.

Should you notice cupping in your hardwood, your first goal is to determine the source of the moisture.  From a visible plumbing leak to a major flood, any water spilled onto hardwood floors should be dried up immediately.  During the summer months, humidity levels should be monitored.  To prevent hardwood floor cupping in a basement, running a dehumidifier is beneficial.

Is there a remedy for cupped hardwood?  Most mild to moderate cupping will improve on its own as the hardwood planks dry.  In flood situations, or where the cupping is excessive, the floor may need to be dried, sanded and refinished.