Log in to view the full article
Floating Advice
I'm installing a solid wood floor over concrete, and I want to do a floating subfloor system. How should I do it?
Steve Seabaugh, technical training director at the NWFA, answers:
The typical floating subfloor system over a slab is two layers of at least 3 / 8 inch plywood. The second layer is laid at a 45 or perpendicular to the first layer and is fastened to the first layer on a 12-inch grid pattern.
However, there is another floating system I really like to use. When I tell people about it, they are hesitant at first, because it sounds so simple, but it really saves on labor and material costs. It is just one layer of 3/4 -inch plywood cut into 16-inch-wide pieces with a 3/4 inch gap in between. The pieces are loose-laid at a 45 or perpendicular to the direction of the floor, and the ends are staggered.
To start a job with this type of subfloor, you need to attach a "bridge" board that runs across and is fastened to each piece of subfloor underneath it. Then you can snap your lines and fasten down your backer board to start nailing and remove the bridge board. Just like with any floor, once you have a few rows nailed, you can remove the backer board. The only limiting factor with this type of floating subfloor is that you can't lay parquet or other patterned floors on it.
The Skinny on Sealers
Is it really necessary to apply a sealer as my first coat when finishing a hardwood floor? I have been applying thr ee to four coats of finish without a sealer and my floors seem to be just fine, but I'm not sure if I might be in for some problems down the road.
Todd Schutte, director of training at Aurora, Colo.-based BonaKemi USA, answers:
A good sealer, whether solvent or waterborne or a suitable stain, usually serves some very specific and specialized functions in relation to the wood and the finish coats. A sealer should penetrate the wood to seal the surface but also sit on top to provide initial build for the finish. Finish used as a sealer will tend to soak in too much, neither fully sealing nor providing initial build. Being the first coat, the chemical makeup of the sealer is also important because it is formulated to not react with extractives, oils and resins in the wood. Finishes, generally being slower drying, will tend to have a greater reaction with these components on the surface and in the seams and soft grain.
Waterborne sealers should provide elasticity and be pH balanced to minimize sidebonding and the pull of tannic acid and other extractives—effects that waterborne finishes used directly on raw wood will tend to exacerbate.
Solvent-based sealers should be quicker drying and thinner than their finish counterparts to minimize reaction with oils and resins, especially in exotic species—again, an effect that straight solvent finishes will have on many species. Some contractors also like to use solvent-based sealers under waterborne finishes to add color and depth to the floor.
Using a wood floor stain and/or the appropriate waterborne or solventbased sealer is the best first step in minimizing reactions between your finishing system and the wood, providing quicker drying and a solid base to build layers of finish upon. The quicker drying and reduced cost of sealers also makes good business sense in cutting the overall time in completing the job and adding to the bottom line.
Radiant Choices
Which types of woods can I install over radiant heat?
Rusty Swindoll, assistant technical training director at NWFA, answers:
Obviously, engineered flooring is a good choice for radiant heat, because its laminated construction makes the flooring much more dimensionally stable than solid products.
If you want a solid wood floor, first, choose a dimensionally stable wood species. American cherry, American walnut and teak are examples of woods that are relatively stable. Species such as American maple and hickory/pecan are two choices that tend to move more and may not work well over radiant heat. Their light color also tends to show the gaps between boards.
You also should think about the cut. Quartersawn and riftsawn cuts are good cuts to use because their expansion moves more up and down rather than side to side. In general, it is not recommended to use solid wood flooring more than 4 inches wide. Some manufacturers do not recommend installing solid wood floors over radiant heat at all, so be sure to check with the manufacturer of the product.
Trick of the Trade
Maximum Output
by Genia Smith
Here is a nifty trick for getting every ounce of glue out of a 1-gallon can. Take the lid off the can and turn the can upside down. Then, use a can opener to cut open the bottom of the can. Next, use the new cut-out "lid" to push the glue out through the can. The lid will scrape the sides of the can as it goes down, leaving you with no waste, even on a 1-gallon can.