Worth 1,000 words

Christopher Capobianco

Teachable moments from others’ mistakes

It is said a picture is worth a thousand words, so here are four pictures of situations I’ve encountered and about a thousand words about these situations that can help floor coverers and specifiers avoid similar failures.


I had a recent site visit to the lobby of an office in New York City to examine “bumps in the floor” in areas where a resilient sheet material had been installed. In the one area, the bumps were hard and uneven, perhaps from a sloppy application floor patch. In another area, there was a perfect square that must have been either an old tile or the remains of adhesive around the old tile. In the area of this photograph (below left), the bumps were soft air bubbles, indicating adhesive failure of some kind.

Turns out the previous floor covering was a resilient tile over plywood. The tile was removed, and the new adhesive went right over the old because, they said, “we had to complete the work over a weekend and had no time for floor prep.” I suspect the two adhesives may have had a reaction with each other and that’s why it let go. Another cause could have been that the floor was wet or otherwise contaminated when the flooring went down. Ugly as it was, this complaint was a simple case of inadequate floor prep — they installed a flexible floor covering over a floor that wasn’t flat and didn’t deal with the old adhesive. This could have been avoided with a little bit of detective work in advance. I would have lifted a few tiles — seeing plywood and adhesive underneath, I would have left the old floor in place, installed a high-quality plywood underlayment over the existing tile and installed the sheet goods over that.


I worked for a major manufacturer in the late 1990s, and we did a lot of seminars for installers, who were often surprised we wanted to teach about “easy-to-install” wall bases and accessories. But, then and now, gaps are a frequent callback that can ruin an otherwise beautiful job.

The two causes are related to the temperature sensitivity of vinyl: product handling and/or acclimation and stretching of the material. When it’s warm, vinyl can stretch during handling and installation. If you throw a box of cove base, reducer, or vinyl plank over your shoulder and it bends, you just stretched every piece in the box. Install it with nice tight joints and when the material adjusts to room temperature and goes back to its original size, there is a gap at every joint. It’s not shrinking after installation; it’s stretching before or during.

The solution, especially in warm weather? Handle carefully and bring the material to the job at least two days before installing it. Lay those 12-foot-long accessory pieces or roll base out flat so they can “relax.”

My second point about stretching is shown in this photo of vinyl T-molding (right). I’ll bet it was a perfect joint when it was installed. However, the installer stretched the material — either intentionally to make a tight joint or unintentionally because the material was warm. It went back to its original size and a gap opened. The proper way is to avoid stretching at all – install the material full, and force it into the joint without pulling. The same goes for glue-down reducers. The adhesive can’t hold vinyl that’s been stretched. Let them acclimate and take care not to stretch the material!


The photo below shows a commissioned inspection I did 10 years ago on a carpet tile installation in a jewelry store. The tile, “designed to be installed without adhesive,” made the job go quickly after-hours, so the owner did not lose any sales days.

However, as the space began to be used, gaps started form at some of the joints. In most of the area, the tiles were tightly fitted and there are no visible issues. The gapping was explained in the part of the instructions the installer had missed. “A fixed and unmoving perimeter is mandatory… to avoid tile movement or shifting requires modules be firmly fitted (within 1/16 inch) to all wall lines or fixed building structures or be anchored with adhesive or double-sided tape around the perimeter and under partial or cut tiles measuring less than 12 inches.”

Bingo. The tiles were not fitted tight to the walls where baseboard moldings had been installed to cover the edges, and small pieces against the walls were not adhered. This allowed the tile to move. Luckily, this was easy to fix by pulling the tile together and adhering the perimeter. Today, there are numerous methods for installing carpet tile: adhesive-free systems with corner tabs that hold tiles together, partial “grid” adhesive patterns that lock the tile in place on large installations, and full-spread releasable adhesives applied by trowel, spray or roller. Before taking a project on, do a little homework on what’s specified and what the job calls for.


Is the photo at right how you are testing concrete for moisture? It used to be common and was even an ASTM test method! However, in 1996, I was part of ASTM Committee F.06 on Resilient Flooring that began standardizing methods and practices for testing and preparing concrete to receive floor coverings. In the 2000s, a scientific “round robin” test of moisture testing methods was undertaken in a lab near Chicago. Under “ideal” conditions (70o F, 50 percent RH), a 500 square foot, 6 in. thick concrete slab was placed for six months so comparisons of every available type of concrete moisture test could be conducted. Calcium chloride kits, relative humidity probes and handheld meters from every manufacturer were placed — plus several plastic sheet tests. I witnessed a calcium chloride test at over 13 lbs/1000sq feet/24 hrs, (over the maximum for any flooring) next to a plastic sheet test that was bone dry, which proved how inaccurate this method was.

Several other “round robin” tests like this over several years helped the manufacturers of moisture testing kits, probes and meters standardize their equipment, and helped the ASTM Committee fine tune the test methods. For example, the ASTM F 2170 Relative Humidity test method is now a one-day test instead of three days that were required when the method was published in 2002, and the F1869 Calcium Chloride test includes specific requirements such as grinding the slab clean before doing the test. The bottom line is that the methodology for moisture testing is better than ever, with published industry standards that mandate testing and specify how it needs to be done, and the awareness of the need for testing is widespread. If you’re not doing testing, you’re going against industry standards and manufacturer warranties, and if you’re testing with ancient methods like a sheet of plastic taped to the floor, you’d might as well not even bother.

I have hundreds more photos of situations I’ve encountered for decades, and stories to go along with all of them. If you like this format for my column, let me know — I’ll be glad to keep them coming!

Christopher Capobianco has been in the floor covering industry since the 1970s in various roles including retail and commercial sales, technical support, consulting, journalism, education and volunteer work. He currently is part of the sales team for Spartan Surfaces in New York City. You can reach him via christopher@SpartanSurfaces.com.

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