Substrate is the surface on which the stone tile will be laid.
Installers can apply the mortar directly to a cement subfloor and simply lay the tile.
Wood subfloors, however, usually require a CBU or cement backer unit for support and a moisture barrier.
Unlikely as it may seem, the substrate material can move. For example, water penetrating the grout or freezing and thawing can sometimes cause tile to rise, crack or chip. To help prevent this, some installers might use a underlayment called Ditra,
which will allow for slight movement of the substrate without damage to the stone floor.
For some high water-absorption stone materials, like some sandstone, travertine etc, you must choose some rapid-setting mortar for installation. Never use cement on the back of these high water-absorption stone materials. Otherwise, it will make some white
shadows come out from the stone tiles after the mortar has fully cured.
Laying Down the Floor
The installer will measure the area and snap chalk lines for an accurate layout. Some pieces will need to be cut to fit a particular shape of the room. These are measured and marked and set aside for hand cutting. The installer then uses a wet saw with a 10-inch diamond blade to customize the stone. Freshly cut edges are smoothed by hand with a smoothing stone.
Once the layout has been determined, thinset mortar, which is a cement-based adhesive, is applied to the substrate surface with a notched or grooved trowel. Each stone or tile is then pressed into place.
Stone tile is typically installed with narrow grout joints — that is, with little space between tiles. If the area to be tiled is large, installers may use plastic wedges or spacers to maintain consistent spacing between each tile. In small areas they may not use these at all.
Don’t worry if your installer insists on a little back butter. That just means each tile or stone piece gets slathered with a little additional thinset to strengthen the bond between the tile or stone piece and mortar already laid on the substrate.
Stone floors are rarely precisely level, but as the installers move along setting the tiles or stones, he or she continually checks to make sure the everything is as level as possible. To compensate for the varying thickness of the stone, the amount of thinset mortar applied is adjusted.
How to Choose Grouts
After the floor is laid and the thinset mortar has fully cured, the installer fills the joints between the tiles with grout. Un-sanded grout is most commonly used in natural stone installations. It fills the small joints easily and won’t scratch soft stones like sanded grout might.
For a uniform look, select a grout color that is a close match to the tile for a tone on tone effect. This will make the room look bigger.
Choosing a shade that is slightly different than the tile color will give your installation more depth and interest.
Consider where the grout is going to be used, a dark shade tends to show less dirt.
To emphasize each tile, choose a grout in a contrasting color. The grout then acts as a frame for each tile giving the installation a grid effect.
The grout mixture is spread over the tiled area with a tool called a float to fill in all the joints. A sponge is used to wipe off the excess. Don’t step on it yet, the grout has to cure, which could take up to 48 hours.
Before the Big Day
Call a friend, hire a team, do whatever you need to do, but make sure you remove furniture and other “stuff” from the room in which your new stone flooring will be installed. You probably don’t want installers handling your precious things — and they may charge you extra for the opportunity.
If you have gas appliances, contact the Gas Company about safely disconnecting and reconnecting these pieces. Ask your retailer about disconnecting and reconnecting such items as icemakers, stereo equipment and computers; and the removal of heavy items like pianos.
Also, consult with your retailer to determine if you will be charged to have your toilet moved out and replaced if your are putting new flooring in your bathroom. If they can’t do it, you may need a plumber.
Good Temps
The area of installation must be climate controlled (heated or air conditioned). Indoor humidity should be maintained between 45-65%.
The Old Flooring
Will your new flooring be installed over your existing floor covering, or do you want your existing floors or carpets removed before the new one is put in? Removal of old flooring or carpeting can be time consuming — and someone has to haul it away and dispose of it responsibly. Be sure to discuss the situation with your installer and assume that at least one day will be spent on removal, cleanup and preparation.
Choose a Trim
In most cases, existing baseboards and moldings have to be removed prior to stone flooring installation. Do you want to keep what you have or go with something new? Be sure to discuss this with your retailer or installer, who may charge extra for removal and reinstallation. Painted baseboards, woodwork and paint may need retouching after the installation is complete. If necessary, this is your responsibility.
An Open Door Policy
Interior doors often have space at the bottom to accommodate flooring. If yours do, then you’re good to go. If yours don’t — or they’re cut for a thinner floor than you install, then you may need a qualified carpenter to cut or shave the bottom of each affected door. Check with your installer about their door policy.
Clean Up
Stone flooring installation results in lots of trash — old carpets or floors, plastic wrapping, remnants, fast food containers. Talk to your retailer or installer about his or her clean up policy — and what is done with leftovers. You may want to save some pieces for other projects.
Take A Day Off
It’s a good idea to be home on the day your new floor is installed. Inevitably, questions will be asked. Decisions will need to be made. And nobody has an eye for the details of your home like you do. So take a vacation day, call in sick, work from home — just be there.
Watch From A Distance
Various tools and methods can make the installation area hazardous to the health of your children and pets. Find a comfortable space in another room or outdoors while the work is taking place.
Conduct A Walk-Thru
Before your installer leaves, walk through the installation area together to ensure that every last detail meets or exceeds your expectations. Ask questions and make sure that you “approve” of both the product and the installation before making your final payment. Remember that stone flooring is a natural product and therefore can never be perfect.
After the Install
If you or your family members are sensitive to dust and odors, make sure the room is well ventilated for the next 48 to 72 hours.
Proper prior planning is the key to a smooth and happy installation.
Choose a good substrate