New Floor Tile Tactics
By Monte Burch
New tools, materials and techniques for this traditional flooring material.
Anyway you put it, laying ceramic floor tile is work—physically, mentally, and in closets and cut-up areas, challenging. New materials and tools, however, can take out some of the hassle.
This kitchen project involved a house well over a hundred years old, with a double layer of vinyl flooring and several problems. The original floor was solid, with a solid-oak underlayment. Over that was a yellow pine finished floor. The pine flooring was well worn. The owners began remodeling about 40 years ago and laid down a 1/4-inch plywood “subfloor” over the pine, then installed vinyl flooring. Years later the old vinyl floor needed replacing. The old floor, however, was solidly stuck in place and impossible to easily remove. So, they simply nailed down another 1/4-inch plywood subfloor and installed another layer of vinyl flooring. To complicate matters, kitchen cabinets were installed over the flooring.
The first step was to remove the molding and quarter round around the cabinet bottom edges. Then a multifunction vibrating tool, such as the Rockwell SoniCrafter or Craftsman Nextec, was used to cut down through the top vinyl and plywood layer, along the cabinet bottom edges. The tool was also used to cut away a small area to be pried up with a pry bar as a starting place. Then, a roof tear-off tool was used to rip up the top vinyl/plywood layer. Sure enough, the old vinyl was still tightly adhered, leaving a good sub-base.
Tile is traditionally installed over an uncoupling layer or forgiving shear interface, a supportive underlayment. An uncoupling layer allows the tiled surface to move independently of, or be ‘uncoupled’ from, the subfloor to prevent cracks in the tiles and grout.
For an uncoupling layer on this project, we used Schluter-DITRA, an innovative underlayment performing multiple functions. Schluter-DITRA is a polyethylene membrane with a grid structure of square cavities, each cut back in a dovetail configuration, and an anchoring fleece laminated to the underside. The product is bonded to the substrate using thinset mortar. The anchoring fleece on the underside of Schluter-DITRA fully engages in the mortar to provide a mechanical bond to the substrate. Tile is installed over the underlayment using a thin-bed method in such a way that the mortar becomes mechanically anchored in the square cutback cavities of the DITRA matting. Designed specifically for ceramic tile and dimensional stone installations, DITRA serves not only as an uncoupling layer but also as a waterproofing membrane and vapor-management layer.
The Schluter-DITRA product performs all these functions while still providing adequate support and load distribution for the tile covering. When placed on a solid foundation, columns or pillars can support tremendous loads. The same physical principle applies to DITRA installations. Column-like mortar structures are formed in the cutback cavities of the matting. Loads are transferred from the tile covering through these column-like mortar structures to the substrate. Since DITRA is virtually incompressible within the tile assembly, the advantages of uncoupling are achieved without sacrificing load-distribution capabilities.
Schluter-DITRA comes in a roll, which is much easier to work with than solid systems. The material is easy to cut with scissors or a sharp knife. Since it’s flexible, it’s easier to get the material into smaller spaces, such as closets and hallways. Cut the material to fit, including cuts for heating ducts and any irregularities, and lay it dry to test the fit.