CEU Resource Center

Tip #1 Controlling Humidity in Homes Not Occupied Year Round

Condominiums or vacation homes are often not occupied a good bit of the year. If the HVAC is turned off, humidity can build up and get between the boards to the underside and cause the floor to cup. It is very low cost to back seal the boards with inexpensive polyurethane before installation. Polyurethane does not encapsulate wood but it does slow down the wood’s ability to take on give off moisture and balances both sides of the wood to avoid cupping.

Tip #2 Handling Wide Board and Large Room Installations

When using wide boards or installing in large rooms (nail down installation), start in the middle and nail toward both walls with spline glued into the grooves of the middle boards. Because the tongue side is held down with fasteners, most of the movement is on the groove side, so you cut the shrink/swell in half.

Tip #3 Installing Wood Over Concrete

We always recommend sealing the concrete, even with engineered wood. It may be dry now; however, you don’t know what will occur after storms or leaks. A well made engineered wood with a water resistant plywood backer and high-quality glues can dry out and will usually be fine if you get the water off relatively quickly, but it can’t dry out unless the concrete is sealed.

Tip #4 Moisture and Installation

Every installer should own a moisture meter. The ones with pins that measure electrical resistance are the best. Orient the pins with the grain when calibrating and measuring. Meters that sit on top of wood measure specific gravity and do not work well on dense reclaimed wood. The only concrete meter that will measure the real moisture content in a slab is the ASTM 2170 type. Calcium chloride tests measure only the top two centimeters. Sit on top concrete meters measure only the top two inches. If excess moisture is deep in the slab, it will equilibrate when covered and cause problems.