Mason:

Our hardwood flooring was buckled in several areas, so we hired a flooring guy to sand and refinish all of it throughout our first floor. Two months later, those same areas have buckled again! What happened, and what do we do now?

Elsie M., Gum Springs

Dear Elsie:

There are several possibilities for this, but (without examining the before and after conditions), I can give you the “90% probability” response…

When the edges are higher than the middle of a wood board, this is known as “cupping”. This condition is typically caused by a higher moisture condition on the bottom of the boards, than on the top. Especially in wet areas such as kitchens and baths, spillage can migrate (through the joints) down to the subfloor, and is not removed nor may it evaporate quickly there. So the bottom of the board swells and results in “cupping”. The opposite, less common condition (crowning) will happen if the moisture conditions are reversed.

If you recall the manner in which your floor boards were “buckled”, it is likely that post-refinishing, the boards are now the opposite condition. The reason is that your previously-cupped boards were sanded flat on top, then over time (when the bottom portion ultimately dried out), returned to its natural state – flat on the bottom and (since the edges were sanded-off) now crowned on the top.

Aargh… I know this is frustrating for you. Your only options now might be, either “live with it”, or re-sand and refinish again. You might get by with only reworking the crowned areas. It is possible to blend-in a newly-refinished floor much more easily than an old one.

A good flooring contractor should be able to check the moisture content with a meter prior to taking more action, to assure that the flooring is now “stable”.

Hardwood flooring is beautiful, comfortable and quite serviceable. However, like most materials of natural origin, it requires some care, and is reactive to environmental conditions – especially moisture. Take steps to protect and care for your hardwood flooring in wet areas, and let’s hope that we can avoid these concerns in the future!

Best,
Mason