In this do it yourself renovation post, we will cover in detail how to lay ceramic tile floor. If you would like to learn about installing ceramic wall tile, visit our post “How to install ceramic wall tile“.
The following are items that you will need to complete the job, from start to finish:
- Wet Saw Ceramic Tile Cutter
- Ceramic Tiles (how to calculate the amount of tiles will be shown later)
- Quarter Inch notched trowel
- Mortar Mixer (this will be used with a hand held drill)
- Grout (I suggest Sanded Grout)
- Large bucket
- Chalk line
- Tape Measure
- Pencil
- Carpenters Square
- Hammer and a couple Common Nails
- Tile Spacers (I suggest ¼”)
When installing tiles on any surface, you need to ensure that it is clean and free of dirt and oil. If you do not make sure the area is clean, you will not get proper adhesion of the mortar mix, and the tiles may lift.
Preparing for installation on a Wooden Floor
If you are installing ceramic tiles on a wooden floor, it needs to be properly supported so the tiles do not lift, move and or crack. To do this, there needs to be a minimum total of 1 ¼” thickness of plywood under the tile. This can be done by installing an extra layer of plywood or cement board on top of the existing floor (aka subfloor). For strength reasons, ensure that the existing wood grain and new wood grain are perpendicular (opposite) to each other.
Preparing for Installation on a concrete floor
There are many products available for laying Ceramic tile on a concrete floor and can be done many ways. Various types of subfloor products are now out on the market, but I prefer the inexpensive way of installing it directly on the concrete floor. You will have to ensure the floor is clean and free of dirt, oil and paint; otherwise the thin set mortar mix will not adhere to the floor properly, resulting in the tile lifting and cracking.
Also, the floor must be somewhat free of high and low areas. An area where there is a low or high point in the floor can be fixed with a product known as floor leveler. This a concrete based material, which is spread on the floor to fill areas in the floor and enable the floor to be somewhat level. Follow the manufacturer’s instructions on floor leveler mixing procedures, and with a mortar trowel spread a thin layer of mortar in the recession in the floor until it becomes level with the area around it. Several thin coats of leveler may be required. If there is an area where there are high protrusions on the floor, floor leveler may not be the most likely solution. You may have to chip away at the area with a masonry chisel or jack hammer and level the area with quick set cement mix and then floor leveler.
Calculating the amount of material needed
Calculating the amount of tile needed is a relatively simple process. Measure the length and width of the room and multiply the two dimensions. This will give you a total square footage of floor space of the measured room. If you are tiling more than one room, measure each room and add the area of each room together. Once the area is found, work out the area. For example, if a room was 13’ x 16’, the total area for the room would be 208 square feet. If you are using a 12” square tile, the total area of one tile is 1 square foot. So, you can simply divide the 208 by 1, therefore the job requires 208 tiles. Although you know that you will need a certain amount of tiles after this calculation, a good rule of thumb is to add 10% to the total for waste and error. This is done by multiplying 208 by 10%, resulting in 20.8 or 21 extra tiles, bringing the total number of tiles needed to 229.
Marking the Floor
The next step is to mark your floor, so your installation can take place. Marking the floor is a very crucial step, so as to keep the tile straight and even throughout the floor. If you are laying the tile running from right to left on the floor at a 90 deg angle to the walls, this is done by measuring the width of the room, finding the center of the floor. A Perpendicular line needs to be marked as well, running in a cross like formation from wall to wall, as shown in illustration. A chalk line is best suited for this job, leaving a nice crisp line on the floor and is a very simple task to perform. The perpendicular lines are made with the chalk line very easily, with or without assistance. Simply drive a nail in the floor at your designated mark and loop the end of the chalk line on the nail, ensuring there is plenty of chalk on the line and stretching the line out to the other mark made. Pull the line tight and snap the line on the floor.
If you are running the floor diagonally on a 45 deg angle, you must find the center and snap lines at a 45 degree angle to the walls.
If you find that the tiles on the outside, near the wall are too small, move the center line of the tile right or left to make the tile on either end larger. This will create more waste, but will eliminate the need for small cuts. Keep in mind that the tiles near the walls should be very similar in size.
Mixing Thinset Mortar
You will need to set up your tools in an assortment that will be practical. For example: your wet tile saw will make a lot of noise, dust and water spray, so you should maybe use it outdoors, in the garage or basement. Fill the wet saw with the required amount of water needed, and mix your thin-set mortar following the manufacturer’s instructions. This should be done with a simple mortar mixing tool that is attached to a drill; the water should be added slowly as you mix, so not to make the mortar mix too watery. The consistency of the mix should be similar to hot oatmeal cereal. A mix that is too watery will dry and become too weak when it sets, and a mix that is too dry won’t adhere to the tile or floor. See pic below for a better understanding.
Laying the Ceramic Tile
In order to start laying the ceramic tile, whether you are laying the floor at right angles to the wall or on a 45 degree angle, as previously discussed. You will start laying the tile beginning with the center, staying on the chalk line that was snapped earlier. You want to start laying the tile from one side of the center line working your way to the far corner opposite the doorway. After-all, once the floor is laid you have to have a way out of the room…and you can’t step on the tiles to do it. See the illustration to get a better understanding of how things work. Some professional ceramic tile installers lay tiles differently from the next. Some do what’s called back-buttering the tile, which includes spreading a thin layer of thin-set mortar on the back of the tile before it is laid in position. On the other hand, some installers don’t practice this procedure. I recommend only back-buttering smaller pieces of tile, and those that will be hard to lay because of the restricted amount of area that you can spread the mortar on the floor with your trowel.
The spreading of the mortar takes a little bit of skill and handiness to be able to do it correctly. The mortar can be scooped out of the bucket with the notched trowel and applied to the floor area where you are going to begin. Once the mortar is down, it is spread with the notched trowel so that it will cover the area of a couple tiles. You should keep in mind that you will need to see your chalk lines, so try not to cover them with the mortar mix. The mortar needs to be spread in such a manner that it leaves ¼” wide ridges along the floor.
Place the first tile on one of the sides of the where the two chalk lines meet, but as I stated earlier, it should be done on the side furthest from the door. After the first tile is laid along the two chaulk lines, you can now start spreading more mortar along the line so that tiles can be laid continuing to the far wall, keeping in mind to use your tile spacers. Use your spacers as much as possible. Sometimes you might not be able to use your spacers because of the contours of your tile or the tiles being different sizes. If it happens that you have to do this, do your best at splitting the distance all the way around the tile and continue with the next tile using spacers.
When you have to cut the tile along a wall, for example, measure and cut the tile so that the tile is approximately 1/4″ away from the wall. Your wet tile saw should come with factory made attachments, such as a rip fence and a device for cutting tiles at a 45 degree angle. My advice is to mark and draw a line on the tile with a permanent sharp tipped marker, where it needs to be cut. This is done to act as a back up in case the rip fence ends up moving, due to pressure and vibrations. If this happens, you must reset the ripfence position on the saw. These are very useful attachments and should be used as often as possible, but is impossible to use all the time.
Cutting Circular Holes in Tile
From time to time, you may be required to cut a hole or square shape in the tile. Sometimes, this can be done by setting your tile in place where it will eventually be installed and mark the sides and center of the two marks, both on the tile and the item you are cutting around. From this mark you can set your measuring tape at the center mark and measure the outside area of object you are tiling around. This can then be transferred to the tile, and cut.
Cutting a circular hole in the tile in this manner can be done with a special tile bit that is made to fit on a drill or rotary tool(as shown in pic). Place the bit center on the center of hole mark on the tile and gently ease your way through, because too much pressure will crack the tile. If are very good with the wet saw, you can attempt to do the same with the saw. This can only be done if the hole that needs to be cut ends up on an outside edge of the tile. My suggestion is to use the proper tile drill bit. 
If you were going to attempt this sort of thing with the wet saw, you will have to make many cuts inside the hole area, making each cut about a 1/4″ from each other. This will make it easier to use the Tile Nibblers to crack off the excess tile. If the hole you are cutting is a toilet flange, you can do a somewhat rough job and still have a good result, due to the toilet covering up most of the area. On the other hand, if you were cutting around a floor drain, you should be very accurate with your cuts and therefore use the proper bit for the job.
Spreading Grout
Once the tile have been laid, depending on the manufacturer, you have to wait approximately 12 hours to spread the grout. Check the thin set mortar’s container or bag for the directions on the product that you are using, as this time frame may vary. Once this time frame is achieved, you can now start mixing your grout in the same manner as you mixed the thin set mortar, using the same tools and procedure. The only difference between mixing the mortar and the grout is the desired consistency, as grout is not quite as runny. Applying the grout in the proper manner is very important, especially in a kitchen or washroom area, where it will be exposed to water. If the grout is not applied properly, water may penetrate in around the grout and get under your tile and into the underlying floor, potentially causing damage.
Spreading the grout is another art in itself, but can be done by anyone that has a good set of arms, because it can become a very tiring process. You want to use your grouting trowel for digging into the bucket of mixed grout and scooping it out and applying it into the grout lines of the furthest part of the room away from the door, once again working your way from the corner to the door. Push and move the grout around into the grout lines and try to level the grout with the top of the tile as much as possible, and don’t be afraid of getting a little dirty.
During this process, you should be wearing gloves and have your bucket of water and grout sponge ready. Do about 4 or 5 tiles with the grout, wiping the grout off the tile as much as possible with the trowel. You will then wet the sponge, ringing it out and wipe the tiles perpendicular across the grout lines, trying to remove the grout from the surface of the tile and leveling off the grout in the lines. Once done, start the process all over applying the grout in the lines and then clean it off with the sponge. When all the floor is done, you will notice the the tile that once appeared clean is now streaked with grout coloring once again. This is normal, and will have to be cleaned a few times with the sponge only, using new water in the bucket each time. A good practice is not to dump the used grout in any of your sinks or toilets. This material will settle in the plumbing traps and harden, causing plumbing blockage problems. During this process, if you notice that you need more grout in a certain area, you can go back and reapply a small amount of grout in that area and start the process in that spot over again.
Finishing the Job
When the floor is wiped of all surface grout and completely clean, you can now start installing your baseboard and casing trim around doors and install the threshold moldings between your different types of flooring materials. This will be covered in detail in future posts, Happy renovations!
