Professional Standards for Large Format Tile Installation

Selecting the Right Adhesive: Standards and Classifications

Quick Reference Guide:

• C1 vs. C2: “C” stands for cement-based. C2 is an “improved” adhesive with double the bonding strength of C1—essential for large format tiles.
• S1 vs. S2: These indicate flexibility (deformability). Large tiles expand and contract; an S1 or S2 rating means the adhesive can flex without cracking the tile.
• T (Thixotropic): This means “non-slip.” It is critical for wall installations to prevent heavy 24×48 tiles from sliding down before the adhesive sets.

Subdivisions

The recommended adhesive for internal flooring in residential and public-use environments is as follows:

ADHESIVE TYPE: PORCELAIN FOR OUTDOOR FLOORING

The recommended adhesive according to the type of substrate is as follows:

ADHESIVE TYPE: PORCELAIN FOR INDOOR WALLS

The recommended adhesive for porcelain tiles on indoor walls and ceilings is as follows:

For walls with radiant heating, the choice of adhesives is as follows:

ADHESIVE TYPE: WHITE BODY TILES FOR INDOOR WALLS

The recommended adhesive for white body tiles on indoor walls and ceilings is as follows:

When the tile is white or light-colored, it is advisable to use a white tile adhesive

For walls with radiant heating, the choice of adhesives is as follows:

Grout Joint Standards and Achieving Minimal Seams

“Note on Large Format: While standards allow for 1/8″, a 1/16″ joint is achievable on perfectly level, stable substrates using professional leveling systems, providing the most seamless aesthetic for 24×48 and 48×48 porcelain. tiles”

GROUTING MATERIAL

Tile spacers and levelling systems must be removed before grouting can begin. .

Grout joints must be empty and clean of any adhesive materials, debris or dirt, and they must have a uniform depth.

• Do not prepare large quantities of grouting material; this will ensure that it is applied as fresh as possible and as unaffected by environmental conditions (temperature, humidity and air circulation) as possible
• If the grout has to fit perfectly into the joint, it should be applied with an extrusion gun and then finished off with a steel spatula.

MOVEMENT JOINTS

1. Tile
2. Adhesive material
3. Levelling layer
4. Substrate
5. Expansion joints

PERIMETER JOINTS

1. Tile
2. Adhesive material
3. Levelling layer
4. Substrate
5. Perimeter joints

INSTALLATION

The thin-bed method entails spreading the adhesive in a thin layer on part of the installation surface, then combing with a notched trowel, always parallel to the short side of the tile.

When tapping the installed tile, the straight trowelling lines help the ridges to collapse and allow air to escape through the ends, preventing the creation of voids and holes without adhesive and improving the bond by ensuring full contact across the entire surface of the tile.

The thin-bed technique offers the following advantages:

• Smaller amount of adhesive required
• It eliminates the risk of errors when preparing mixtures
• Faster, more effective installation

BACK-BUTTERING METHOD

SPACERS AND LEVELLING SYSTEMS

CUTTING AND DRILLING

Linear cuts: standard porcelain stoneware cutting tools can be used. Cut the surface of the tile from one end to the other without stopping and applying steady, uniform pressure.

Once the incision has been made, apply gentle pressure on either side to break into two pieces

Holes: To drill holes smaller than 10 mm in diameter, use an electric drill with an appropriate bit. Do not use hammer mode, and operate at a low rotation speed. Do not exert excessive pressure on the surface of the tile.

For holes larger than 10 mm in diameter, use a hole saw. Start drilling with the tool at a slight angle to the tile. These tools can be used either wet or dry.

Square / Rectangle holes: to make square holes for junction boxes, sockets, etc. it is recommended to use an electric tile cutter with a continuous diamond cutting blade. Before cutting, use a drill to make holes at the corners of the shape to be cut.

To ensure a good finish and prevent sharp edges, it is important to finish them off with an abrasive sandpaper.

“Never make the square holes through the underside of the tiles or go past the edges of the hole with the electric cutter.“

Avoid “L” and “U” shaped cuts, since they can lead to cracks and breaks in the future; proper planning is crucial here.

FLOOR INSTALLATION

Check that the ambient temperature lies between 5 and 30ºC, during both the installation and the curing time of the cementitious adhesive

The surface must be completely dry and clean of grease, oil and dust, with no traces of cement, resin, paint, or loose particles.

The surface should be perfectly flat. It is essential to fill in any uneven parts using suitable products to achieve a perfectly level floor.

The surface must be completely dry and clean of grease, oil and dust, with no traces of cement, resin, paint, or loose particles.

• Floor should have the necessary strength and mechanical resistance for the stresses it will have to withstand in the intended use.
• Make the necessary perimeter joints and expansion joints and respect the structural joints
• When installing on top of existing floor tiles, make sure they are solid, stable and well bonded. Before installing the new flooring, the existing floor tiles should be properly cleaned.

APPLICATION OF THE ADHESIVE AND TILE INSTALLATION

Follow the manufacturer’s recommendations and prepare the mixture using an electric mixer to ensure a homogeneous product with no lumps.

Spread the adhesive over the installation surface and the underside of the tile (thin-bed technique with back-buttering), working in small sections. First spread the adhesive across the substrate with a 1/4″ – 3/8″ trowel and then “comb” it (spread the adhesive evenly) with a 3mm (1/8″) notched trowel on the back of the tile.

To help trapped air escape, the adhesive should be spread in the same direction on both the back of the tile and on the substrate, aligning with the direction of the shorter side of the tile.

Tap each tile vigorously with a rubber mallet or vibrating compactor to ensure they are properly bedded.

Lay the tiles flat exerting a slight pressure and insert the clips at the ends of the tile (approx >2″ from the edge).

After laying the adjacent tile, manually insert the wedges into the clips. Then, using the appropriate tool exert maximum pressure to level the tile before the adhesive sets.

Periodically lift up installed tiles to check for full coverage of the adhesive, which will guarantee a good bond in the future. Wait at least 24 hours after finishing laying the floor before beginning to fill the joints.

Remove the clips one by one with pliers to ensure the correct extraction (do not hit the wedges).

• When placing the clips, keep a distance of 2″ to 3″ mm to the edge of the tile.
  
• The recommended distance between clips is <10 “
• For floors with radiant heating, check that the heating is turned off 48 hours before laying the tile and do not turn it on again until 7 days after the completion of the grouting, to avoid drying out the adhesive and the grouting.
• Take precautions against any weather conditions that may impair the proper setting of the material.

APPLICATION OF THE GROUT

Select the grouting material to be used depending on the width and the required physical and chemical properties.

• Apply the grout with a rubber grout float.
• Clean the joints with a wet sponge or similar before the material sets.

INSTALLATION ON INDOOR WALLS

• The surface must be completely dry and clean of grease, oil and dust, with no traces of cement, resin, paint, or loose particles.
• The surface should be perfectly flat. It is essential to fill in any uneven parts using suitable products to ensure it is plumb.
• It must be compact, stable, with no cracks and have set correctly. If the substrate is unstable or has slight cracks, the use of an anti-fracture membrane between the substrate and the tile is recommended.
• It should have the necessary strength and mechanical resistance for the stresses it will have to withstand in the intended use.
• To install on top of existing tiles, make sure that they are solid, stable and fixed to the wall. Before installing the new tile, the existing tile should be properly cleaned.

• It is advisable to use a grout joint of at least 1/16″, for both rectified and unrectified tiles, and to respect all movement joints.
• Follow the manufacturer’s recommendations and prepare the mixture using an electric mixer to ensure a homogeneous product with no lumps.

It is advisable to apply adhesive in small sections, spreading it evenly with a 1/4″ – 3/8″notched trowel.

The use of the thin-bed technique with back-buttering is recommended; do not use spot bonding to lay tiles. Use a 1/8″ notched trowel

Place the tiles on the fresh adhesive, pressing them down and making a light back-and-forth movement to ensure maximum coverage of the underside, respecting the intended grout joints.

Once laid, settle the tiles into place using a clean rubber pad, and tapping it with a rubber mallet.

Place the tiles on the fresh adhesive, pressing them down and making a light back-and-forth movement to ensure maximum coverage of the underside, respecting the intended grout joints.

• When placing the tiles, manually insert the wedges into the clips.
• Wait at least 24 hours after finishing laying the floor before beginning to fill the joints.

• Select the grouting material to be used depending on the width and the required physical and chemical properties.
• Apply the grouting material using a rubber grout float.

Clean the tile with water and cleaning products, using cloths, sponges and plastic brushes.

• Under no circumstances should a ceramic till be installed without a joint, or “butt-jointed”.
• Use spacers to ensure regular joint size.
• Tiles should not be immersed in water.