Vinyl tile confusion
In today’s world of vinyl tile, it’s easy to get confused. As the vinyl tile category continues to grow, I see confusion among installers about installation methods, adhesives and floor prep.
Some of it is just the nature of so many different terms being tossed around these days; VCT, VET, HVT, Solid Vinyl, Quartz tile, “Luxury” Vinyl, “Click” Vinyl, WPC, “PVC Free”…. It’s no wonder we can’t keep it straight!
Since I covered “floating” floors earlier this year, I’ll talk about products that are installed with adhesive this time.
Vinyl Composition Tile (VCT) hasn’t changed much in recent years, but I still see a lot of different results when I see VCT floors. There are also a lot of assumptions that continue to be made, often affecting these results.
A VCT assumption that I find puzzling is that less substrate preparation is needed with VCT than for other types of resilient flooring. This is not true! I’ve seen many “lumpy bumpy” VCT floors as a result of assuming you don’t have to prepare for their installation.
Flat and smooth is important with all resilient floors. It’s maybe even more important for VCT, because if the substrate is not flat or there are cracks or movement, the tile can crack.
Another situation is assuming that VCT is somehow “more tolerant” of concrete moisture conditions. This leads to a lot of jobs with gapping seams or adhesive oozing between the seams.
Moisture limits for VCT are no different than other vinyls, so be sure to do your moisture testing, as always.
That same gapping condition can be caused when any type of vinyl, including VCT, is installed in very warm conditions.
The tile can expand a little when warm and then goes back to its normal size when the air conditioning is turned on. The gapping is blamed on “shrinkage” but is actually the material reacting to changes in temperature. It can happen to VCT and SVT as well. I’ve especially seen a lot of this with vinyl plank, vinyl base and edgings.
Rectangular materials can be stretched when handling or installing and when they “relax” after installing, gaps can occur.
“Quartz” composition tile is a variation on VCT that uses pulverized quartz instead of limestone as the main ingredient. Since quartz is a much harder mineral, these products are very high performance when it comes to indentation resistance but also are harder to cut. Luckily, they have a higher vinyl content than VCT so it’s a much more flexible tile that’s often made in 24-inch squares. That’s a time saver for installation to be sure.
Make sure you have the right adhesive for quartz, because the typical VCT adhesive probably does not cross over into this category.
“Luxury” vinyl tile (LVT) can be confusing because the term “LVT” does not necessarily describe a specific type of product. The two vinyl categories according to ASTM are VCT and solid vinyl tile (SVT). Some so-called LVT products may be more like VCT in the backing and SVT types have a vinyl backing.
The inner layers of the SVT products may be anything from almost VCT-like to a very high vinyl content that’s harder to cut. It’s good to know that beforehand so you can allow the right amount of time.
The adhesive for each of these is very different, and depending on the application it may require a wet-set adhesive, pressure-sensitive or transitional adhesive. What’s the difference?
A lot of installers prefer pressure-sensitive because they can spread a large area of adhesive at one time, let it dry so that it’s tacky, and then install the tile and work on top of the tile. On the other hand, a wet-set can only have a small amount of adhesive spread at one time so that you lay the tile while the adhesive is still wet, working off of the tile as you go.
This is more challenging, but is often a preferred method for some types of solid vinyl, PVC-free, rubber, and other materials because it’s a much harder set that lends itself better to these types of products, especially in very high traffic. Transitional adhesives are somewhere in between pressure-sensitive and wet-set.
They allow an open time of generally 20 to 30 minutes until they are slightly set but still slightly wet. This for me is the best of both worlds, because it’s a little more installer-friendly and still gives very hard set characteristics.
Which adhesive will be right for any given floor will depend on the product and also on the end use of the floor. When in doubt, be sure to check on the recommendations before the tile and adhesive are ordered, and if you’re still not sure make that phone call to the manufacturer for clarification.
I realize it’s more difficult to have to keep all different types of adhesive available, but with so many different products today in the vinyl category you really need to make sure that what you’re installing and the adhesive that you’re installing it with are compatible.
The results can be a failure. For example, I’ve seen cases where a VCT “clear then spread” adhesive was used to install solid vinyl tile, and the edges of the tile curled.
PVC-free is another category that’s growing right now. There is a demand by some owners and architects for non-vinyl floors. This has usually meant rubber or natural linoleum, but there is a growing number of polyolefin-based products that look like vinyl but are not.
These can be sheet products in a chip look, but also wood-look planks and other stone-look tile that are identical in appearance to so-called LVT. However, they are not identical in composition so take the time to get to know what you are dealing with. They are generally a lot more stiff than vinyl tile, so cutting can be more time consuming.
And, once again, adhesive selection is critical. Vinyl adhesives will not adhere these products so be sure to use the manufacturer’s adhesive, and pay attention to the adhesive application method; some are wet set and some are not!
Speaking of adhesive, I’ve said it here many times but it bears repeating. In addition to not following the recommended methods of application (pressure sensitive, wet set and transitional), the size of the trowel is a huge cause of failures. By that I mean the wrong trowel. More often than not, it’s too large a trowel notch for a lot of these products, which causes adhesive oozing, indentations in the finished floor and worse. With the high-performance adhesives being produced today, LESS is better in many cases!
That 1/16-inch VCT trowel is going to put down way too much adhesive if you are installing vinyl back material. Of course, the porosity of the floor has a lot to do with this, but the important thing is to be ready.
Most concrete is not very porous so a smaller notch is preferred. You’ll use less adhesive, get a good strong bond and prevent some of the other problems.