Laying Floor Tiles

Floor Tile Basics:

Laying Floor Tile

In This Article: Cement backer board is laid, a careful layout line is drawn, mortar is applied to the backer and tiles are set in place.	Related Articles: Index of Flooring Articles Installing Cement Tile Backer Grouting Floor Tiles
Skill Level: 2-3 (Basic to Moderate)	Time Taken: 2 Hours

By Bruce W. Maki, Editor

This article explains the procedure of installing floor tile in a simple room, in this case a closet. In our old house remodeling project we earlier laid marble tiles on the floor in two bathrooms. The smaller of those baths had a 3'x3' closet. Since we did not have enough spare marble tile to do that small additional area, we decided to use inexpensive ceramic tile.

We purchased some plain beige 6"x6" tiles for 25 cents each, or $1 a square foot. That's much cheaper than the marble tiles which cost $6 per square foot.

I had already vacuumed the floor and painted it with oil-based primer.

The marble tile was 1/2" thick, over 1/4" WonderBoard. Since the ceramic tile for the closet was only 1/4" thick, I needed to use a thicker cement tile-backer board.

I cut out a piece of 1/2" Durock to fit in the closet, and tested the fit before mixing any mortar.

I applied a layer of thin set mortar to the floor, using the smooth edge of the trowel to force the mud into the cracks in the floorboards.

Using the notched side of the trowel (1/4" x 1/4" square notches) I combed the mortar into a series of ridges.

I laid the Durock into place, which was sort of difficult because I had to work around some obstructions on the walls.

The 1/2" Durock in place. I stepped on the cement board to press it into the mortar.

I drove in some Rock-On brand of cement-board screws. Some people use roofing nails to install cement-board. When I've used nails, I've made sure to hit the floor joists.

In this case the 1Ľ" screws aren't long enough to reach the floor joists, since the flooring is 7/8" thick and the Durock is 1/2". I placed the screws about 8" apart.

At the seam I applied a strip of fiberglass mesh tape (red arrow). This was covered with mortar as soon as I began to lay tiles.

The completed Durock, ready for ceramic tile.

Laying out a straight reference line for the tiles is crucial, especially in large rooms. I used a 12" speed-square to obtain a right angle, and aligned a chalk line with the edge.

In larger rooms (and any tile job would be a larger room than this) this reference line should be laid out carefully, possibly using a 3'-4'-5' triangle to obtain a very precise right angle.

Tile Time:

I spread some thin set mortar on the Durock, be careful not to obscure the chalk line. First I used the smooth edge to squeeze the mortar into the rough surface.

Then I used the notched side to comb out the mortar. The ridges are necessary to give you the ability to push the tile down into the mortar. Otherwise the mortar would ooze out around the edges.

Where the ceramic tile met the marble, I clipped off one leg of the plastic spacers

I laid a couple of tiles against the spacers, and added more spacers as I progressed. These spacers act as a reliable guide, keeping the gap uniform and keeping the tiles aligned.

These are 3/16" spacers that I'm using.

Any size of spacer can be used, depending on the desired look.

The first few rows took only a few minutes.

I reached the back wall rather quickly.

I wanted to lay tiles against the blue chalk line so I could ensure that the pattern would be perpendicular to the marble tiles.

Now, if I was doing a large room with only one entrance, I would of course start laying tile at the back of the room and work outward. Sometimes the only practical approach is to lay tiles on one half of the room during the first day, so you can walk on them the next day when finishing the job.

After about 20 minutes I had laid all of the full-sized tiles.

I used a permanent marker to lay out the cuts on the partial tiles.

For a larger tile job, where you can't reach the cut pieces without walking on the tile, this would be the stopping point for the day. The next day the tiles can be walked upon, and the cut tiles can be laid.

Before going outside to the tile saw, I sprayed a little mist on the wet mortar, to discourage it from skinning over.

This sprayer is a neat little garden chemical sprayer that pumps up with air. About $7 at Home Depot.

Cutting Tile:

This tile saw by PlasPlugs costs around $100 and is well worth the money, even for just a few rooms. It comes with a 4" diamond blade.

One side is removable so water can be added. The diamond blade is partially submerged during operation, so the blade stays cools and dust is virtually eliminated.

The PlasPlugs saw cuts through tile fairly quickly. This machine may not be fast enough for tile professionals, but it's plenty fast for me.

I also cut a dozen thin strips for the small pieces needed around the edges of the closet.

The PlasPlugs saw has a simple plastic fence that works surprisingly well.

I set the cut tiles in place.

I debated whether to even bother with the 3/4" wide strips of tile around the edges, since the baseboard will likely cover them. But it took so little time to cut the strips, I just did it.

I scraped off the excess mortar that had slopped on the walls. Then I wiped the walls with a damp cloth.

After the mortar had begun to set (about an hour after laying the tile) I used a small screwdriver to scrape out the mortar where it oozed up between tiles.

The finished tile job, before applying grout.