DIY Help Topics

Find answers to all of the most commonly asked tile and stone DIY questions.


1/8” or larger

Grout joints 1/8” or larger are typically used for floors. Choosing a wider grout joint for a tumbled stone installation on a wall can intensify the rustic appeal. When grouting joints 1/8” or larger, a sanded grout is recommended. MAPEI Keracolor S and Ultracolor Plus are considered to be sanded grouts. MAPEI Flexcolor CQ and Kerapoxy CQ grouts use a special type of coated sand and can be used in most installations where a sanded grout is recommended.

1/8” or smaller

Grout joints 1/8” or smaller are typically recommended for glossy wall tile, polished stone, glass tile and mixed material mosaics. Choosing a narrow grout joint on a floor with rectified edge porcelain can help to achieve a more monolithic appearance. When grouting joints 1/8” or smaller, typically an unsanded grout such as MAPEI's Keracolor U is recommended. MAPEI Flexcolor CQ and Kerapoxy CQ grouts use a special type of coated sand and can be used in joints as small as 1/16” wide. MAPEI Flexcolor CQ and Kerapoxy CQ grouts can be used most installations where an unsanded sanded grout is recommended, however, a test is always recommended to confirm compatibility.

Additional Products

To complete the job, a flexible sealant such as MAPEI Keracaulk S, Keracaulk U or Mapesil T will be required in grout joints that are considered to be areas of movement. Areas of movement include changes of plane such as a tub/tile line or countertop/backsplash line or the corners of shower walls.

In addition, it is a good idea to seal cement-based grouts such as MAPEI Keracolor S and Keracolor U with a high quality sealer such as MAPEI UltraCare Penetrating Plus, Stone, Tile & Grout Sealer.

Backsplash

A backsplash behind a sink on a bathroom wall can add an element of luxury to the room. A backsplash behind a stove can be a simple way of adding a personal touch to the kitchen. Either way – a backsplash is a great project for a first time do-it yourselfer! Choosing a stain resistant grout such as MAPEI Flexcolor CQ will help make kitchen maintenance easier. For optimum stain resistance, an epoxy-based grout such as MAPEI Kerapoxy CQ is recommended.

Bathroom

A bathroom remodel can increase the value off your home. With careful planning you can complete some of the work yourself and save money.

Bathroom floors on second story areas require special consideration. Tub overflows can result in damage to building materials and finishes on floors below. Applying a waterproofing membrane like MAPEI AquaDefense is an easy way to help contain excess water and protect lower floors from water damage.


Calculating Area

Properly calculating your project’s total area helps ensure an accurate estimate of the materials needed. The shape of your project space may require combining multiple measurements. Follow the simple directions on our Calculating Total Area page to guide you through the process.

Cement Board

Cement board is a good choice for most installations of tile and stone on shower walls, tub walls and floors. It is important to install cement board in strict accordance to the cement board manufacturer’s written instructions.

Floors: installation instructions for cement board on floors typically include applying cement-based thinset between the exterior grade plywood and cement board. The cement board is then screwed into the plywood while the thinset is fresh/wet. MAPEI recommends the use of Porcelain Tile Mortar or Ultraflex 2 as thinset under the cement board. If leveling is needed on interior cement board floors, MAPEI recommends the use of a pourable leveler such as MAPEI Self-leveler Plus or Novoplan Easy Plus over the cement board. MAPEI Primer T or ECO Prim Grip should be used to prime the cement board before the use of a pourable leveler.

Walls: installation instructions to treat corners and seams on cement board on walls typically include using a self-adhesive mesh tape and thinset. MAPEI recommends the use of Porcelain Tile Mortar or Ultraflex 2 in conjunction with mesh tape recommended by the cement board manufacturer.


Cement Pavers

Cement pavers are made by pouring concrete into a mold. They can vary in thickness from about 1” to 3” and typically resemble brick or natural stone.

Setting: MAPEI recommends Uncoupling Membrane Mortar mixed with Polymer Additive or Kerabond T mixed with Keralastic additive for setting the pavers over concrete.

Grouting: Since cement pavers are commonly at least 1” thick, special considerations should be made when grouting. MAPEI Ultracolor Plus grout is recommended for grouting cement pavers. As an alternative method, grout joints can be partially filled with one of the setting mortars above – leaving ¼” depth of the joint open for grouting. After 24 hours, pavers can be grouted using MAPEI Keracolor S or Flexcolor CQ grouts.


Ceramic

Ceramic tile is made from clay. A glaze is applied to the top surface and then the tile is fired at a high temperature. The glaze creates the color and pattern of the tile. The durability of the glaze on ceramic tile can vary greatly. As opposed to Porcelain tile, Ceramic tile is generally quite porous and therefore is generally not recommended in exterior freeze/thaw zones. 

Wood Look Plank Tiles and other tiles with one side longer than 15" - when installing ceramic wood look plank tiles, use a mortar that is designed for very large tile such as MAPEI Large Tile & Stone Mortar or Ultraflex LFT. Since grout color is a major factor in achieving the realistic aesthetic appearance of a real wood floor, it is important to select a color-consistent grout such as MAPEI Flexcolor CQ or Ultracolor Plus FA.


Ceramic Wall Tile

Ceramic wall tile is commonly used for kitchen backsplashes and tub walls. It is typically less than 12” in size. Since it is designed for use as wall tile, it is usually not well suited for floors as the glaze or finish of this tile is not typically resistant to scratching or wear from foot traffic. Check the PEI rating of the tile for durability.  Because it is typically easier to scratch than tiles designed for the floor, Ceramic wall tile is best grouted with MAPEI Keracolor U unsanded grout.

Also see Glossy Wall Tile

Clean Drywall

Drywall has a paper or water-resistant covering over a core that is made of gypsum. It is a common building material used to construct interior walls in dry areas. Drywall should be installed in strict accordance to the manufacturer’s instructions and local building codes. It is best suited for interior dry areas only as some building codes do not allow the use of drywall for shower walls or tub walls.

Drywall seams are patched and filled with a gypsum-based patching compound commonly known as “wall mud”. Since gypsum and cement are not compatible, it is important to prime all drywall surfaces with a primer such as MAPEI Primer T or ECO Prim Grip prior to installing tile.

If drywall has been painted, it is best to cover it with cement board or remove and replace it with new drywall or new cement board.


Concrete

Concrete is made from a mixture of cement and aggregates. It is primarily used in construction and is often a substrate for floors. Since concrete is made from a mixture of cement and aggregates, it is very compatible with cement mortars for tile.

All concrete substrates should be clean, dry and free of dust, dirt, oil, grease, paint, tar, wax, soap, concrete curing compounds, concrete color stains, concrete sealers, clear coats, loosely bonded toppings, any primers that are not MAPEI brand, old adhesive residues (unless otherwise recommended by MAPEI), and any other substance that may prevent, reduce or affect adhesion or performance.  Drop a few drops of water on your concrete to see if it absorbs.  If it beads up and doesn't soak in, the concrete likely has a sealer or wax.


Countertop

Since countertops are closer to eye level than floors, skillful craftsmanship is the key to a professional-looking installation. For this reason, it is a good idea to make all the tile cuts and place the tile in position without adhesive or mortar before installing – this is called dry fitting. With a little extra time spent carefully measuring and planning the installation, you can create a terrific work surface that you will be proud of!

Choosing a stain resistant grout such as MAPEI Flexcolor CQ will help make kitchen maintenance easier. For optimum stain resistance, an epoxy-based grout such as MAPEI Kerapoxy CQ is recommended.


Cracks

Hairline cracks (very thin cracks) will often occur in new concrete slabs due to shrinking and are not typically a cause for concern. However, all existing cracks should be examined as certain types of cracks can be a sign of a more serious issue. When examining existing cracks, there are three main things to look for:
  1. Is the crack “flat” or is one side of the crack higher than another?
  2. Is the crack short in its length or does it span from one outside wall to another?
  3. Is the crack old and has it become wider over time?
If the crack is flat, short in length or is old and has not moved, the application of a crack isolation membrane like Mapelastic AquaDefense or Mapelastic CI is recommended. However, if the crack is not flat, if it spans the length of the structure or if it has become wider over time, an inspection by an experienced professional engineer is recommended in order to determine appropriate repair procedures.

Delicate Glass

Some glass tiles are more sensitive to scratching, such as glass tiles that have soft glass and glass tiles that have an iridescent finish. These delicate glass tiles should only be grouted with an unsanded grout like MAPEI Keracolor U. Adding MAPEI Grout Maximizer to Keracolor U will help to reduce the porosity of the grout and help to keep the grout clean.  Other glass tile may work just fine with Ultracolor Plus FA or Flexcolor CQ, grouting a test area first and evaluating it for scratches is the best approach when dealing with glass.

Existing Ceramic Tile

In order to tile over existing, well-bonded ceramic tile, the tile should be lightly sanded and then cleaned. New ceramic or porcelain tile can then be installed with a polymer modified mortar such as MAPEI Ultraflex 2 or Porcelain Tile Mortar or Large Tile & Stone Mortar or Ultraflex LFT.

If sanding is not possible, then the existing ceramic tile should be cleaned and then primed with MAPEI ECO Prim Grip. New ceramic or porcelain tile can then be installed with a polymer modified mortar such as those listed above.

When doing tile-over-tile for a shower floor, a drain extender will be required to raise the drain to the level of the new tile.


Existing Epoxy Coatings

Existing epoxy coatings on floors should be cleaned and primed with ECO Prim Grip. New ceramic or porcelain tile can then be installed with a polymer modified mortar such as MAPEI Ultraflex 2 or Porcelain Tile Mortar or Large Tile & Stone Mortar or Ultraflex LFT.

Existing Laminate

Existing laminate material on countertops and backsplashes should be lightly sanded, cleaned and primed with ECO Prim Grip. New ceramic or porcelain tile can then be installed with a polymer modified mortar such as MAPEI Ultraflex 2 or Porcelain Tile Mortar or Large Tile & Stone Mortar or Ultraflex LFT.

Existing Non-cushioned Sheet Vinyl

Existing non-cushioned sheet vinyl that is well-bonded should be lightly sanded and cleaned. Then tile can be installed using a two-part mortar such as MAPEI Uncoupling Membrane Mortar mixed with Polymer Additive or Kerabond with Keralastic.


Existing VCT (vinyl composition tile)

Existing VCT should be cleaned with a commercial wax stripper, neutralized with plenty of water, allowed to dry completely and then primed with MAPEI ECO Prim Grip primer. New ceramic or porcelain tile can then be installed with a polymer modified mortar such as MAPEI Ultraflex 2 or Porcelain Tile Mortar or Large Tile & Stone Mortar or Ultraflex LFT.

NOTE: VCT that was installed prior to 1981 should be tested for asbestos. MAPEI products are not recommended or warrantied over any substrate that contains asbestos.


Exterior

Tiling a patio can help transform a backyard into a fun outdoor living space for relaxing or entertaining. Outside areas require special materials. If your project is outdoors, uncovered and located in a climate that experiences temperatures below 32° F, a two-component mortar such as MAPEI Uncoupling Membrane Mortar mixed with Polymer Additive or Ultraflor mixed with Keralastic additive are the best choices. It is also a good idea to consider the planned use of the area. For example, if you plan to use the space as an eating area, a stain resistant grout such as Ultracolor Plus FA or MAPEI Flexcolor CQ is a great choice.


Exterior Grade Plywood

Exterior Grade Plywood is also known as exterior glue plywood. It’s crossply construction and water-resistant glue makes Exterior Grade Plywood the industry’s best choice for tile installations over a wood substrate. Tile installations over plywood are limited to interior floors in dry areas only.

Floors: Exterior Grade Plywood floors should consist of a double layer of plywood, glued and screwed together. Each layer should be a minimum of 5/8” or 3/4” thick, to equal a minimum of 1 1/4” total thickness. The floor should be very solid and stable with no deflection (bounce or movement). Any deflection issues should be corrected prior to installation. Plywood should be free of paint. If plywood has been painted, paint should be mechanically removed. Old flooring glue should be scraped down to a thin residue. Remaining glue residue should be primed with MAPEI ECO Prim Grip primer. Minor low spots in plywood can be corrected by filling these areas with a cement-based patching compound such as MAPEI Planipatch. If leveling is needed, MAPEI recommends the use of a pourable leveler such as MAPEI Self-leveler Plus or Novoplan Easy Plus. MAPEI Primer T or ECO Prim Grip should be used to prime the plywood before the use of a pourable leveler.

All exterior grade plywood substrates should be clean, dry and free of dust, dirt, oil, grease, paint, tar, wax, clear coats, loosely bonded toppings, any primers that are not MAPEI brand, old adhesive residues (unless otherwise recommended by MAPEI), and any other substance that may prevent, reduce or affect adhesion or performance.


Fireplace

Tiling a fireplace can be a simple way to update the look of your living area. Since fireplaces are occasionally used as heat sources, special materials are needed for long-lasting installations.

For glass tile, stone tile, or mixed material mosaic, a two-part mortar such as MAPEI Mosaic & Glass Tile Mortar mixed with Polymer Additive or Mosaic & Glass Tile Mortar mixed with Keralastic is recommended.

For porcelain and ceramic tile or mosaic a two-part mortar such as MAPEI Uncoupling Membrane Mortar mixed with Polymer Additive or Kerabond with Keralastic additive is recommended.


Floor

Replacing old carpet on a floor with new tile is a great way to increase the value of your home. Tiling floors can take some time, so it is a good idea to break down the project into several stages.

Even before you begin to tile, it is important to determine if your substrate is suitable to receive a tile installation. All deficiencies must be corrected prior to beginning to install the tile.

It is critical to use the correct setting material and the correct trowel for the tile that you have selected. When you are installing the tile on the floor, make sure that you check for proper mortar coverage by periodically lifting a couple of tiles and inspecting them for coverage. Mortar should cover the entire back of the tile without voids or trowel lines. Give yourself plenty of time for grouting – it’s often the most difficult and labor-intensive part of the installation.


Glass Tile

Glass tile is made from pouring melted glass into molds or fusing pieces of glass together with heat.

Some glass tiles have unique backings or coatings and require special types of setting materials. Always follow the glass tile manufacturer’s written installation instructions.

For all other glass tiles, MAPEI recommends Mosaic and Glass Tile Mortar. When installing glass tile in a pool or when installing glass tile over waterproofing membranes such as AquaDefense, mix MAPEI Mosaic and Glass Tile Mortar with Polymer Additive or Keralastic.

When grouting glass tile, an unsanded grout such as MAPEI Keracolor U has the least likelihood of scratching the tile. If a sanded appearance is desired, a colored quartz (CQ) grout such as MAPEI Flexcolor CQ or Kerapoxy CQ or a fine aggregate cement grout like Ultracolor Plus FA can sometimes be used successfully, but a test panel should be grouted and inspected for unacceptable scratching before grouting. Delicate glass tile should only be grouted with an unsanded grout like MAPEI Keracolor U. Adding MAPEI Grout Maximizer to Keracolor U will help to reduce the porosity of the grout and help to keep the grout clean.


Glossy Wall Tile

Glossy wall tiles have shiny and delicate finishes. For this reason, an unsanded grout such as MAPEI Keracolor U is recommended. Adding MAPEI Grout Maximizer to Keracolor U will help to reduce the porosity of the grout and help to keep the grout clean. If a ready-to-use grout such as Flexcolor CQ is selected, always test a spare piece of tile to confirm compatibility.


Grout Joint Width

Grout joint widths are an important factor in a successful tile installation. When choosing spacer size, consider the aesthetics of the installation, the type and size of tile, the edge style of the tile and the type of grout.

3/16” is a standard size joint width. Wider joints may be needed with installations of very large tiles. Even installations of small tile require a minimum of 1/16” grout joint.

Our calculators divide grout joints into <1/8" (where an unsanded grout like Keracolor U is best) and >1/8" (where a sanded grout like Keracolor S can be used).  Specialized grouts such as Flexcolor CQ, Kerapoxy CQ, and Ultracolor Plus FA have their own limitations on grout joint widths.


Honed & Tumbled Stone

Honed and tumbled stone can be great choices for backsplashes where a relaxed, rustic décor is preferred. Honed and tumbled stones should be sealed before grouting to prevent grout pigment from staining the surface of the stone.

Honed natural stone has a matte, dull finish as opposed to the shiny, reflective finish of polished stone. Honed stone is sanded only until the cut marks are removed.

Tumbled natural stone has an aged, worn look. Tumbled stone goes through a mechanical process that weathers the stone until a distressed look is achieved.  This typically results in rounded edges.


Laundry Room

Laundry rooms on second story areas require special consideration. Water spillovers from clothes washers can result in damage to building materials and finishes on floors below. Applying a waterproofing membrane like MAPEI AquaDefense is an easy way to help contain excess water and protect lower floors from water damage.


Leveling

An easy way to determine how much leveling is needed is to place a carpenter’s level on a long straight edge and then measure the space (depth) of the lowest areas.

A self-leveling underlayment such as MAPEI Self-leveler Plus or Novoplan Easy Plus is a pourable product that helps correct a substrate that is out-of-level. Self-leveling underlayments require very solid, stable substrates. Since, self-leveling underlayments have short working times, it is a good idea to have at least 3 people working together when pouring a self-leveler; one to mix the product, one to carry the buckets and pour and one to spread the leveler and guide it into the desired areas as it is poured.

A primer such as Primer T is always required when using MAPEI Self-leveler Plus or Novoplan Easy Plus.


Liquid Waterproofing Membrane

A liquid waterproofing membrane such as MAPEI AquaDefense can often be used as a replacement for a PVC liner. When using a liquid waterproofing membrane such as AquaDefense, it is important to follow all instructions on the label and Technical Data Sheet as well as local building codes.

Note: Premixed adhesives like MAPEI Type 1 Mastic and premixed mortars like Premium Mortar for Tile & Stone should never be used over liquid waterproofing membranes.


Masonry

Masonry substrates include brick and concrete block walls.

All masonry substrates should be clean, dry and free of dust, dirt, oil, grease, paint, soap, clear coats, any primers that are not MAPEI brand, old adhesive residues (unless otherwise recommended by MAPEI), and any other substance that may prevent, reduce or affect adhesion or performance.


Mixed Material Mosaic

Mixed material mosaics (mixed media mosaics) include combinations of small glass, stone and/or metal tile. When installing mixed material mosaics, MAPEI Mosaic & Glass Tile Mortar mixed with Polymer Additive or Keralastic is recommended. Always follow the mosaic tile manufacturer’s written installation instructions.

When grouting mixed material mosaics, use an unsanded grout such as MAPEI Keracolor U. Adding MAPEI Grout Maximizer to Keracolor U will help to reduce the porosity of the grout and help to keep the grout clean. If a sanded appearance is desired, a colored quartz (CQ) grout such as MAPEI Flexcolor CQ or Kerapoxy CQ or a fine aggregate grout like Ultracolor Plus FA can sometimes be used successfully, but a test panel should be grouted and inspected for unacceptable scratching before grouting.

It may be necessary to pre-seal any honed or tumbled stones in the mosaic before grouting to prevent grout pigment from staining the surface of the stone.  Ultracare Penetrating Plus Stone, Tile, and Grout Sealer is recommended.


Mosaic

Mosaic tiles can be made of glass, porcelain, ceramic, polished stone or honed stone as well as a variety of other natural and man-made materials.

Mosaic tiles are very small or tiny tiles – usually about 1” x 1” in size. They are typically sold in sheets where each small tile is adhered to a mesh backing. The actual size of the tile refers to the average size of each individual tile – not the size of the sheet. When installing mosaic sheets, the space between each sheet should mimic the spacing between the individual tiles in order to create a clean, uniform look.


Mud Bed

A mud bed (mortar bed) is used to create the slope on the shower floor. A sand & cement mix serves as the material for the mud bed. When the sand & cement mix is mixed with water, it is called a dry pack. The dry pack should be the consistency of wet beach sand, just as you would use to make a sand castle from a plastic mold. This consistency allows you to shape the mix precisely to the required slope.


Patching

Concrete and exterior grade plywood substrates on floors that have occasional low spots (bird baths) should be patched and filled with a cement-based patching compound such as Planipatch.


Polished Stone

Polished natural stone has a shiny, reflective finish as opposed to the matte, dull finish of honed stone. Polished stone is sanded with finer and finer grades of sanding discs until a glossy finish is achieved.

When grouting polished natural stone, use an unsanded grout such as Keracolor U. Adding MAPEI Grout Maximizer to Keracolor U will help to reduce the porosity of the grout and help to keep the grout clean. If a sanded appearance is desired, a colored quartz (CQ) grout such as Flexcolor CQ or Kerapoxy CQ or a fine aggregate cement grout such as Ultracolor Plus FA can sometimes be used successfully, but a test panel should be grouted and inspected for unacceptable scratching before grouting.


Porcelain

Porcelain tile is made from high-quality clay and fired at an extremely high temperature. It can be glazed or unglazed. With unglazed porcelain tile, the color of the tile is the same from top to bottom – this is called through body porcelain tile. Unglazed porcelain tile is sometimes polished like marble to achieve a shiny, reflective finish. With glazed porcelain tile, a glaze is applied to the top surface and then the tile is fired. The glaze creates the color and pattern of the tile. The durability of the glaze on porcelain tile can vary greatly. Check the durability rating of the tile to make sure it is suitable for your installation. Sometimes porcelain tile is cut a second time after it is fired in order to achieve a perfect square edge. This type of porcelain is called rectified edge porcelain.

Porcelain tile is generally considered to be impervious (non-porous) and therefore is highly recommended in exterior freeze/thaw zones.  Due to the low porosity of porcelain tile, MAPEI recommends polymer-modified mortars for installation.  The Products page gives a list of these mortars.

Wood Look Plank Tiles - when installing porcelain wood look plank tiles, use a mortar that is designed for very large tile such as MAPEI Large Tile & Stone Mortar or Ultraflex LFT. Since grout color is a major factor in achieving the realistic aesthetic appearance of a real wood floor, it is important to select a color-consistent grout such as Flexcolor CQ.


Preformed Base

A preformed base like the MAPEI Shower Base, eliminates the challenging and time consuming task of creating a slope with a mud bed. A MAPEI Shower Base can be custom ordered to fit a variety of dimensions and drain locations.


PVC Liner

A PVC liner is a vinyl waterproofing membrane that comes in a sheet and is placed over the pre-slope on a shower floor. The pre-slope is the first layer of the mortar bed (mud bed). The PVC liner is then topped with a second layer of mortar to create the main slope.


Rough Concrete

Rough concrete will have a surface texture like sand paper. This type of concrete is typically very porous and requires minimal preparation.

All concrete substrates should be clean, dry and free of dust, dirt, oil, grease, paint, tar, wax, soap, concrete curing compounds, concrete color stains, concrete sealers, clear coats, loosely bonded toppings, any primers that are not MAPEI brand, old adhesive residues (unless otherwise recommended by MAPEI), and any other substance that may prevent, reduce or affect adhesion or performance.


Shower Floor

Tiling a shower floor is an advanced level installation project. So, it is a good idea to break down the project into several stages and then spread out the stages according to your experience, physical ability and skill level. The project can be simplified by using a pre-made shower base in order to create the slope.

Remember: proper waterproofing is one of the most important steps of any shower floor project and it is essential to a long-lasting installation. 

Selecting tile for a shower floor is an important consideration.  Smaller pieces (less than 6" on a side) like mosaics tend to be preferable to larger pieces, especially when sloping to a center drain.  


Shower Wall

Tiling walls in an individual shower is an intermediate level installation project. The more time that is spent in design, preparation and planning, the easier your installation will be. Tile and grout are not waterproofing, MAPEI AquaDefense may be required. Also remember the rule: measure twice and cut once. The use of ledger strips and spacers will help establish and keep the spacing of the tile.

Use non-sag mortars such as MAPEI Large Tile & Stone Mortar (white for glass and stone) or Ultraflex LFT (white for glass and stone) to help keep the tile from slipping downwards. An unsanded grout like MAPEI Keracolor U is typically recommended for most tiles that will be used on a shower wall. Adding MAPEI Grout Maximizer to Keracolor U will help to reduce the porosity of the grout and help to keep the grout clean. Flexcolor CQ and Ultracolor Plus FA may also be suitable grouts depending on the type of tile installed.  Sealing both the grout and stone with a quality sealer such as UltraCare Penetrating Plus Stone, Tile & Grout Sealer will help to maintain the installation and make cleaning easier.


Slope

Slope is an essential component in shower floor construction because it guides the flow of water towards the drain.  The slope (pitch) is the gradual descent in the angle of the shower floor. Typically a shower floor should drop 1/4" in height for every 1' of horizontal distance (check local building codes). A sand & cement mix such as 4-to-1 Mud Bed Mix typically serves as the material for the mud bed which is used to create the slope.  Preformed slopes can also be used to ease installation.


Smooth Concrete

Smooth concrete will have a surface texture like a laminate countertop. Smooth concrete surfaces should be tested to confirm porosity. If the concrete absorbs water, then it is considered to be porous. Smooth, porous concrete surfaces should be primed with ECO Prim Grip primer. Ceramic or porcelain tile can then be installed with a polymer modified mortar such as MAPEI Ultraflex 2 or Porcelain Tile Mortar or Large Tile & Stone Mortar or Ultraflex LFT.

All concrete substrates should be clean, dry and free of dust, dirt, oil, grease, paint, tar, wax, soap, concrete curing compounds, concrete color stains, concrete sealers, clear coats, loosely bonded toppings, any primers that are not MAPEI brand, old adhesive residues (unless otherwise recommended by MAPEI), and any other substance that may prevent, reduce or affect adhesion or performance.


Stone

Natural stone is a product of nature and includes granite, marble, travertine, slate, limestone, quartz, basalt, and onyx. These stones are quarried, cut to size, and polished, honed, or tumbled.  Porous stone such as travertine and limestone should be sealed before grouting to prevent grout pigment from staining the surface.

All natural stone should be sealed with a high quality sealer such as UltraCare Penetrating Plus Stone, Tile & Grout Sealer after installation. Even dense stones such as granite can contain porous areas that will be susceptible to staining if not sealed. Sealers are not permanent, so follow the sealer’s directions regarding reapplication for the best results.


Substrate

The substrate is the basis for the tile assembly. Professional tile installers will tell you that a tile installation is only as good as what it is bonded to. So, before planning a tile project, it is important to determine if your substrate is acceptable to receive a tile installation. If your substrate is not structurally sound, solid and stable, it is recommended that you replace it with an appropriate material. The most commonly recommended substrates for tile installations are: cement board, exterior grade plywood (floors only), masonry (walls), and concrete.

All substrates should be clean, dry and free of dust, dirt, oil, grease, paint, tar, wax, soap, concrete curing compounds, concrete color stains, concrete sealers, clear coats, loosely bonded toppings, any primers that are not MAPEI brand, old adhesive residues (unless otherwise recommended by MAPEI), and any other substance that may prevent, reduce or affect adhesion or performance.


Tile

Today tiles come in a variety of types, sizes and shapes and there are thousands of different tiles on the market to meet a wide assortment of tastes, budgets and styles. When selecting a tile, consider that the tile will look different when it is installed next to other tiles and it is grouted. For this reason it is always a good idea to create a sample board (mock up) with the tile and grout that has been selected.

The size of the tile is determined by the measurements of its width and length. Your mortar choice should always reflect the longest edge. For example: many wood look plank tiles are 6” wide by 24” or longer. So, the mortar that is selected for this installation should be recommended for a tile that is at least 15” long (in industry terms, a large and heavy tile) such as Large Tile & Stone Mortar or Ultraflex LFT.


Trowel Size

There is never a "one size fits all" when it comes to proper trowel selection in tile installations. Selecting the right trowel depends on many different factors.  As a general rule, after tile is pressed into mortar, mortar should cover the entire back surface of the tile. If there are voids or trowel lines showing, a larger sized trowel may be required for the installation.  When using premixed products, avoid using a trowel that is too large as it extends the drying time of the adhesive.  Here are some guidelines to help you select the right trowel for your project:

Flat Trowels - Trowels without notches or "flat trowels" are good for spreading patching compounds. They are not recommended for spreading mortar or adhesive in order to install tile except to be used to flatten the ridges when installing glass tile.

Notched Trowels - Trowels with tiny notches such as 1/8" x 3/16" x 1/8" U-notched trowels are generally recommended for tiny mosaic tiles - 1" x 1" or less in size.

Trowels with small notches such as 3/16" x 3/16" x 3/16" V-notched trowels are generally recommended for small tile 1" x 1" to 4" x 4" in size.

Trowels with 1/4" x 1/4" x 1/4" square notches are generally recommended for tile 4" x 4" to 8" x 8" in size.

Trowels with 1/4" x 3/8" x 1/4" notches are generally recommended for tile 8" x 8" to 12" x 12" in size. Back buttering is typically recommended for tile 12" or larger on any one side.

Trowels with 1/2" x 1/2" x 1/2" notches are generally recommended for tile 12" x 12" to 18" x 18" tile. They are typically also a good choice for 6" x 24" wood plank look tiles.  Back buttering is typically recommended for tile 12" or larger on any one side.

Trowels with extra-large notches such as 3/4" U-notched trowels are generally recommended for large tile 18" x 18" to 24" x 24" in size.  Back buttering is typically recommended for tile 12" or larger on any one side.  Installations of tile larger than 24" x 24" require the skill of a knowledgeable and experienced tile installer.

Note: the Technical Data Sheet and product packaging will provide coverage for typical trowel sizes.


Tub Wall

Tiling a wall above a bathtub can help turn an outdated bathroom, into a fresh and renewed space in your home. Some home center installation services can even install new cement board above the tub for you!

For a beginner level installation project, choose small ceramic wall tile such as 3” x 6” subway tile with lugs. Lugs are like built-in spacers. They allow tiles to be placed tightly together with a predetermined small joint for grout. A premixed tile adhesive such as Type 1 Mastic or Premium Mortar for Tile & Stone works well for small ceramic wall tile over cement board. Using a premixed grout such as MAPEI Flexcolor CQ adds additional convenience and simplicity to the installation. If you decide to add a layer of waterproofing over the cement board, then you will need to use a polymer-modified cement based mortar such as Porcelain Tile Mortar or Ultraflex 2.

An unsanded grout like MAPEI Keracolor U is typically recommended for wall tiles, mosaics, and glass tiles. Adding MAPEI Grout Maximizer to Keracolor U will help to reduce the porosity of the grout and help to keep the grout clean.

If you are an experienced installer, selecting a large 12” x 24” porcelain tile for tub walls will create a sleek, contemporary appeal. MAPEI Large Tile & Stone Mortar or Ultraflex LFT products are recommended for large and heavy tiles on walls. An epoxy grout such as Kerapoxy CQ or a grout that doesn't require sealer like Flexcolor CQ is the best choice for wet areas and is also the easiest to maintain.


Type of Substrate

There are many different materials used in home construction today. However, only a handful of these materials are suitable as substrates for a tile installation. The most commonly recommended substrates for tile installations are: cement board, exterior grade plywood (floors only), masonry (walls), and concrete.

Existing flooring such as ceramic tile, VCT (vinyl composite tile) or non-cushioned sheet vinyl can also sometimes serve as suitable substrates.


Type of Tile

There are many different types of materials used to manufacture tile. The most common types are: ceramic, porcelain and natural stone.

Some of the factors to consider when selecting the type of tile are: color, pattern, edge style, shiny or matte surface, durability of finish, glazed or solid surface, slip resistance and of course – price.  The type of tile is important when selecting the proper mortar and grout, MAPEI manufactures speciality mortars that work with a variety of tile types.


Waterproofing

The main purpose of waterproofing is to prevent the intrusion of water and moisture in unwanted areas. All shower floors must have waterproofing.

Waterproofing is also an important step in installations such as second story bathrooms and laundry rooms where excess water and moisture may occur.

MAPEI recommends AquaDefense for most areas where waterproofing is required.