Hardwood Floors April/May 2017

CHECK YOUR KNOWLEDGE RESOURCES

1. Which moisture retarders should be used on top of concrete substrates? A. Minimum of 6-mil construction-grade polyethylene film B. Double felt; two layers of #15 asphalt saturated felt paper that meets ASTM Standard D-4869 C. Chemical retarder or urethane membrane, as recommended by the adhesive or wood flooring manufacturer D. All of the above 2. You need a moisture retarder when installing solid strip wood flooring over a concrete slab when the slab is which of the following? A. 3 pounds or less on calcium chloride test B. More than 20 years old C. Above grade D. All of the above

3. If a concrete subfloor does not meet flatness requirements, which of the following should you do? A. Grind subfloor flat

B. Fill low areas with approved patch C. Use a self-leveling concrete product D. All of the above

4. When nailing down a plywood subfloor, which statement is not accurate? A. Fasteners must be 2” from the edge and every 8”-10” along the perimeter B. Use 19/32” CDX plywood C. Allow 3/4” expansion at all vertical obstructions D. Allow 1/8” expansion between all panels

HOW DID YOU DO? See suggested NWFA University learning path on the next page. Answer key is on page 101.

5. Solid wood flooring should be installed where? A. Below grade B. On grade only

C. Above grade only D. On or above grade

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