Q: Our shared-wall townhouse was flooded when our neighbor’s washing machine overflowed. The concrete foundation is apparently not that even, and the water puddled in the middle of our place.
Disaster cleanup folks got most of the mess cleaned up, but there still is a problem in one room with wood flooring. Workmen removed some spongy boards in the flooring, directed heaters on the spot, and then glued down some new flooring three days later.
The new boards warped. They removed them, and a day later laid some new wood, which was then refinished with the entire floor. This also warped. The workers blamed the still-wet concrete and said we need to install new floors.
This room has a built-in bookcase, desks, and file cabinets. The flooring people wanted to install the new floor around this furniture, finishing it off with quarter-round molding. I would not agree to this plan, because if I change the furniture around I would need to install a new floor.
So the floor man removed the warped boards again, and I told him I wanted this area to dry out for a few weeks. My question: Do you think this will do the trick?
A: In a word, no.
The concrete slab is most likely untreated with any kind of water repellent. Water from the neighbor’s washer seeped under the wood floor and percolated into the untreated concrete.
The water is not isolated to the spot where the boards are bad. Dampness probably extends several feet around the repair area. The covered area retains moisture between the slab and the floor. Pointing a heater at the concrete dried only the surface of that area. When new wood covered the concrete, moisture migrated to that area, wicked up into the flooring and warped it.
Completely removing the old flooring and allowing the slab to dry for several weeks, then installing the new floor is the way to avoid further warping. As added insurance, we suggest the wood be brought on site several weeks before it is installed so that it will acclimate to the ambient moisture level in the house.
So that’s the bad news.
The good news is that fitting the floor around your built-ins and using base shoe molding around the edges is a good idea. If the flooring contractor leaves a small gap between the wall/built-ins and does not nail the base shoe to the flooring, the wood will have room to expand and contract, lessening the chance of warping if there’s residual moisture in the slab.
A glue-down floor is not a good idea; use a floating floor system that snaps together to allow for moisture fluctuation in the slab.
Don’t worry about replacing the entire floor if you decide to change the furniture. That won’t be necessary. Any competent flooring contractor will easily be able to patch the gaps left by the furniture.
Installation is a matter of weaving in new boards with the old. Random boards in the existing flooring are cut back and new boards are woven in so that the joints don’t align.
If using raw wood, staining and finishing is easy. Just make sure to keep some of the stain from the installation to use when you decide to reconfigure. If you use prefinished flooring, buy extra to use for the patches.