When it comes to installing wood flooring, sometimes, a homeowner will come along with a request that pushes the boundaries of what normally is done. That’s exactly what happened when Abraham Saucedo of A Custom Floors in Houston, Texas, was approached by a homeowner adamant about a specific approach to affixing new hardwood flooring to their concrete subfloor.
“The homeowner was thinking ahead to when they may want to install new flooring decades from now,” explains Saucedo. “They did not want to have to worry about removing any tar or adhesive from the concrete if the time came for them to replace the floor in the future.”
The request to install a new floor so that it could be removed easily in the future was a request Saucedo had never encountered before, but he was up to the challenge. In his region of the country, most of the floors they install are tar-and-screed systems, where they lay 2×4 screeds in hot tar, which then becomes the new subfloor. Floating plywood is not common in this area.
“I told them that we could do it; however, it was the first time I had done an installation like this, over floating plywood, with nothing nailed down or bonded to the concrete,” says Saucedo. “I had to contact the NWFA to learn how this should be done.”
Saucedo knew rushing the installation process could lead to mistakes and that by following NWFA Installation Guidelines, it would ensure a successful and satisfactory outcome. Using the advice from the NWFA, Saucedo’s approach was to do a floating subfloor system with 6mm plastic laid over the concrete, followed up with one layer of ¾” plywood.
The technical department at NWFA referred Saucedo to the Installation Guidelines on page 77-78, where it details how to install single and double-layer subfloors over concrete. The guidelines define which type of subflooring should be used, how thick it should be, and how it should be installed. They also learned to avoid overlapping seams from one layer of plywood to the next, as well as which fasteners and fastener schedule to use when joining the two panels together. Even more comforting to Saucedo was knowing that all of the floors at the NWFA headquarters were installed over this exact same subflooring system.
“Using this method, it would be critical to make sure the concrete preparation was done carefully and properly throughout the 6,000-square-foot home. That means getting rid of old tar that was there in some areas. It also meant leveling some areas,” says Saucedo. “After first removing the old solid red oak flooring, tile, and carpet throughout the home, we cleaned old tar off of the subfloor with a diamond brush, and used MAPEI Quickpatch to ensure the floor was flat, and within NWFA tolerances.”
After they finished, his team was forced to take a break for several months while the other trades were working. Saucedo and his team later re-entered the home and did additional concrete preparation, slightly abrading the concrete and carefully cleaning it to ensure there was no dust or contaminants left on the concrete.
“With the concrete subfloors prepared, we laid down 6mm plastic, making sure it was installed 10” to 12” up the wall, and above the baseboard so that moisture could not intrude. We then laid down the first layer of plywood. This involved making some custom cuts to accommodate angles,” says Saucedo. “We laid a second layer of plywood opposite to the first layer to bring the floor to an appropriate height. We screwed and glued the second layer of plywood to the first layer.”
After doing the second layer, Saucedo’s team had to wait another six weeks before they could get back to work due to more work being done by other contractors.
“When we returned, there was a lot of dust and debris, so we had to clean it again before we could do the glue-down and nail-down installation of the 9/16” and 9” wide flooring, which was a European white oak with a wire-brushed look with an oil finish,” says Saucedo. “Installation involved using MAPEI Ultrabond ECO 995 with a moisture barrier, and then nailing down. The installation took two weeks, and by that time, almost everything was finished except for minor touch-ups and a final cleaning.”
For Saucedo, the most important lessons he learned were the importance of reaching out for assistance where needed and the critical importance of learning a new installation process. Floating subfloor systems are common in many applications, even floors that are installed to last a lifetime. Although Saucedo knew these people probably wouldn’t actually tear out their floor in the future, it was that piece of mind for them to know that they could.
“It took us more than one year to do this project due to all the other plumbing and electrical work going on in the home. By following manufacturer and NWFA guidelines, we were able to get the floor installed properly,” says Saucedo. “While the wait was sometimes long, the result was nothing short of stunning.”
For additional information about subfloors, check out the NWFA’s Installation Guidelines at nwfa.org/technical-guidelines/.
