It seems that when you discuss resilient flooring among installers, it never fails that substrate preparation and seams are always on the top of the discussion list. In this issue, we will look at a resilient sheet vinyl installation that has seam issues and discuss how to minimize some of the problems we see in the field.
Photo 1 displays a gapped seam next to the awl. The forceps are pointing to a seam that does not fall in the grout line. Photo 2 displays the misalignment of the grout line where the installer placed the seam. Seams were constructed using double cut technique.
Let’s look at the problems of this installation.
• The seam was not constructed in the grout line,
as shown in Photos 1 and 2.
• The area that is displaying a gap at the grout
line was caused by the start and stop of the knife
where the straight edge did not align to continue
the cut along the seam when the installer moved
the straight edge to continue his cut, as shown in
• There is visible contamination in the seams, as
shown in Photo 1.
• In Photo 2, the installer did not align the fill
piece properly prior to double cutting, and thus
the staggered grout line, also the seam does not
fall in the grout line area.
• No seams were sealed.
Here are some methods that may help to minimize some of the problems that are shown.
To properly align grout lines prior to double cutting a felt back rotogravure product, cut out small windows to assist in aligning the patterns, cutting on the outside of the grout line.
As shown in Photo 3, cut these out every three to four feet. To best assist in aligning the grout lines, gently place the point of a sharp double-edged utility blade, which is also used for double cutting, along the edge of the grout line at the window, lift the top layer of vinyl and check alignment with the layer underneath. Once the seam is aligned, double cut following the manufacturers recommended procedures.
used for double cutting, along the edge of the grout line at the window, lift the top layer of vinyl and check alignment with the layer underneath. Once the seam is aligned, double cut following the manufacturers recommended procedures.
I have inspected several installations where the installer stops and moves the straight edge to continue double cutting and leaves a slight gap at the stop/start point. First, make sure that the straight edge is level; this will allow for a clean vertical cut. You may need to place a scrap piece of the material you are working with under one side of the straight edge to level. If there are grout lines that intersect along the length of the seam, when stopping to reposition the straight edge, try to stop with the knife blade at the intersecting point of the two grout lines before moving the straight edge to continue; this will help minimize that slight visual “nick” that occurs and moves it to a more inconspicuous location (Photo 4).
Many installers try to leave the knife in place when they stop to move the straight edge trying to avoid this problem only to have the knife fall out; if this occurs, gently place the knife back into the seam and place it at the stop point and align the straight edge to the knife and grout line. The method of stopping at the grout intersection is just one method to help minimize the visibility of those little “occurrences” that occasionally happen. You can use some blue tape or masking tape and pull the vinyl together at that area if a slight gap appears.
Apply adhesive and use a seam roller at seams and the recommended weight roller for the entire installation.
Prior to sealing seams, the installer must clean the contaminants out of the seam, which is usually the adhesive that was used to adhere the flooring to the substrate. Many installers only clean the surface area and then place the fin (depending on manufacturer) in between the seam and drag the contaminants all along the seam, which can create a seam failure. Here is a tool that I have found that works well to clean seams and not affect the integrity of the seams (Photo 5). Place a slight amount of isopropyl alcohol, or product that the manufacturer recommends, on a white cotton towel for cleaning the seams and the knife blade. Dull the point slightly to avoid the knife gouging or slicing the vinyl or digging into the substrate. Place the knife in the seam and gently pull or push, whichever works the best for you (Photo 6). Pull the knife out frequently to clean the blade. You may need to wipe the surface of the vinyl with a cleaner that the manufacturer recommends. Some of the contaminants may be drawn to the surface by the knife; be careful to avoid rubbing the contaminants back into the seam while cleaning the surface. After you have cleaned the seam, seal the seam using the manufacturer’s recommended seam sealer and seam applicator. There are systems utilized by some manufacturers that also help to minimize contamination at the seams.
In the October 2019 issue of FCI, INSTALL’s executive director John T. McGrath, Jr. and instructor David Gross share key lessons to ensure concrete polishing jobs are done right the first time, every time.