An installer lays Southern Wood Floors' Antique Heart Pine flooring at a home in Atlanta.


Site grading and sprinkler head placement make lateral moisture intrusion a near certainty in this situation.
We are all at the mercy of the unforeseen. Therefore, it makes sense for us to prepare for the foreseen. The “foreseen,” for purposes of flooring professionals, includes the possibility of mishaps occurring. Typically, these mishaps come in the guise of job-related complaints.

Over the years, I’ve seen my fair share job failures. In this article, I’ll discuss a few of the insights I’ve gleaned from such situations. Hopefully, they’ll help you avoid similar problems.

Site inspection. Most often, flooring dealers and even installers totally disregard any jobsite inspections. Perhaps that’s because we feel problems that may develop later as a result of poor site construction are not our responsibility. And that very well may be true. But why would you want job failures of any kind to reflect negatively on your image, especially when you work so hard to establish a good one?

One wood manufacturer, if not more, says the ground of the jobsite should slope downward at least 6 inches for every 10-foot interval leading away from the structure.

Also, before the flooring installation commences, be sure to check the irrigation system. Some landscaping system installers position sprinkler heads practically against the building and, in many cases, they install too many sprinkler heads. Basically, this is done in an effort to save the shrubs and plantings they have placed around the foundation. But ultimately, that vegetation may be saved at the expense of your flooring. Lateral moisture migration has wrecked a lot of floors.

Crawlspaces, in relation to the underside of the joists, must be 24 inches above the ground. A vapor barrier, consisting of a black 6- or 8-mil polyethylene sheet, must also be placed on the soil. Individual polyethylene sheets must be overlapped and taped.

Though not the easiest or fastest procedure to perform, the calcium chloride test can reveal exactly how much moisture is passing through a slab.
Underlayments. Cork, when used as a subfloor, should have a minimum density of 11.4 lbs. per cubic foot. The thickness of the cork should be 1/4 inch or less.

Ceramic tile. All surfaces should be abraded. Grout joints in excess of 1/16 inch must be filled with a Portland cement leveling compound.

Acoustic concrete. This material is heavily filled with gypsum. It should have a strength of 2,500 lbs. per square inch (PSI) and the surface first must be coated with a primer/sealer to ensure a satisfactory wood floor installation.

Wood. The preferred subflooring for a wood floor installation is 3/4-inch CDX grade plywood or 3/4-inch oriented strand board (OSB) PS2-rated underlayment. Underlayment panels should be spaced 1/8 of an inch apart.

Acceptable moisture content for wood subfloors varies by manufacturer. For example, one producer says moisture content may range between 6 and 10 percent. Three other manufacturers state that moisture content should be less than 14, 13 and 12 percent, respectively.

Resilient. Resilient floors that will be allowed to remain in place beneath a wood installation must be cleaned and stripped to ensure a good bond. Make certain that the resilient material is well bonded and consists of no more than a single layer of vinyl.

Concrete. Concrete curing compounds must be removed, preferably by abrading (bead blasting is highly recommended). One producer requires a 3,000 PSI concrete slab for a satisfactory installation.

New concrete must reach a stage of curing where all excess water has left the slab. One manufacturer says you must wait six weeks for the concrete to reach the appropriate stage of cure. Others do not suggest a time frame but do say that moisture tests should be conducted. One organization says a moisture test should be conducted even if the concrete slab is 2 years of age or older.

When a phenolphthalein moisture test is performed, a chemical reaction tat produces a red or pink color indicates the presence of moisture and alkali in a concrete slab.
Moisture testing. Most suppliers recommend a variety of methods for testing for moisture. Among these tests are the ANSI rubber mat or plastic test. Another alternative is testing with an electronic meter such as the types manufactured by Delmhorst, Tramex and Wagner.

Another testing method that yields fast results is the application of a 3 percent phenolphthalein solution in alcohol. To perform this test, chip the concrete, place a few drops of the solution in the chipped area and observe whether the phenolphthalein changes to a pink or red color. If it does, the test indicates the presence of moisture and/or alkali. In such cases, you then should perform the ASTM 1869-98 calcium chloride test to determine exactly how much moisture is passing through the slab. Most producers set a maximum limit of 3 lbs. When an electronic moisture meter is used that figure should not exceed 4.5 lbs.

Leveling. Another pre-installation priority is the leveling of concrete surfaces. Again, different flooring manufacturers recommend different requirements. For instance, one supplier specifies 1/8 of an inch within an 8-foot radius. Another calls for 3/16 of an inch in that 8-foot radius, and still another says 3/16 of an inch in 10 feet or 1/8 of an inch within a 6-foot radius is acceptable. Of course, all parties say that corrective measures should include surface grinding or the application of a Portland cement leveler.

Always remember, complaint handling is non-productive. When handling a wood floor job, try to keep these pre-installation priorities in mind. If you do, hopefully, you’ll only have to worry about the unforeseen.