A successful natural stone installation starts before mortar is mixed. Confirm that the material is appropriate for the intended application, inspect the entire order and coordinate the installation system with a qualified professional.

Before installation:

• Verify the product, size, finish and quantity.
  
• Confirm that all cartons belong to the intended order.
  
• Inspect the material for shipping damage or visible concerns.
  
• Review stone from multiple cartons.
  
• Confirm that the substrate is suitable and properly prepared.
  
• Select compatible mortar, grout, membrane and sealer products.
  
• Complete any required waterproofing before setting tile.
  
• Plan transitions, movement joints, drains and perimeter conditions.
  
• Keep additional material for cuts, selection and future repairs.
  

Do not install material that you believe is incorrect, damaged or unsuitable. Installation generally indicates acceptance of the material’s visible characteristics.

Natural stone varies from piece to piece. Differences in color, veining, mineral deposits, shade, texture and surface movement are inherent characteristics of natural stone rather than manufacturing defects.

Open and inspect material from multiple cartons before installation. Dry-lay a representative portion of the order in good lighting so the installer and project owner can review and approve the overall blend.

During layout:

• Mix pieces from several cartons.
  
• Distribute lighter, darker and more heavily veined pieces.
  
• Avoid concentrating similar markings in one area.
  
• Rotate pieces when it improves the visual flow.
  
• Identify cuts and highly visible locations in advance.
  
• Set aside questionable pieces before mortar is applied.
  

Do not install the tiles carton by carton without first reviewing the overall range. Intentional blending creates a more balanced and natural-looking finished surface.

Natural stone tile should be installed over a substrate that is structurally sound, clean, dry, stable and sufficiently flat for the selected tile format.

Remove dust, oil, curing compounds, paint, loose material and other substances that could interfere with adhesion. Existing cracks, excessive movement, moisture conditions and uneven areas should be evaluated before tile installation begins.

Large-format stone generally requires a flatter substrate than smaller tile because thin-set mortar is not intended to correct substantial floor or wall irregularities. Tile follows the plane of the surface beneath it, so an uneven substrate can contribute to lippage, poor mortar coverage or an inconsistent finished appearance.

The installer should verify:

• Substrate flatness and structural stability
  
• Deflection requirements for natural stone
  
• Existing cracks and movement
  
• Moisture conditions
  
• Crack-isolation or uncoupling requirements
  
• Waterproofing requirements
  
• Compatibility between the substrate and installation system
  
• Applicable building codes and industry standards
  

Never use tile, mortar or grout as a substitute for a required waterproofing system.

Use setting materials specifically approved by their manufacturer for the selected stone type, tile size, substrate and application.

A high-quality white mortar is commonly selected for light-colored or translucent natural stone because darker setting materials may affect the stone’s appearance. Some moisture-sensitive stones may require a rapid-setting, epoxy or other specialized installation system to reduce the possibility of curling, warping, staining or discoloration.

Before installation, confirm compatibility among:

• The natural stone
  
• The substrate
  
• Waterproofing or crack-isolation membranes
  
• Mortar or adhesive
  
• Grout
  
• Flexible sealant
  
• Stone sealer
  

Do not assume that a product labeled “tile adhesive” is suitable for every natural stone. Always follow the latest technical data sheet and written instructions from the installation-material manufacturer.

Avoid premixed organic adhesive or mastic unless its manufacturer specifically approves it for the exact stone and application.

Establish the layout before setting the stone. Identify focal points, centerlines, borders, transitions, niches, drains, plumbing penetrations and other architectural conditions.

A well-planned layout should:

• Minimize narrow cuts in prominent locations.
• Maintain balanced visual lines.
• Account for dimensional variation in natural stone.
• Coordinate grout joints with surrounding surfaces.
• Preserve required movement and perimeter joints.
• Distribute natural color and veining intentionally.
• Confirm finished elevations at adjoining materials.
  

Grout-joint width should be selected based on the stone’s dimensional variation, edge treatment, tile size, substrate flatness and intended application. Do not force naturally varying stone into joints that are too narrow to accommodate the material.

Never install natural stone with the edges tightly touching unless the selected installation method and applicable industry standards specifically permit it.

Mix and apply the mortar according to the manufacturer’s instructions. Do not add extra water or retemper mortar after it begins to set.

Use a trowel size and installation method capable of achieving the mortar coverage required for the application. Key the mortar into the prepared substrate, comb it consistently and apply a thin coat of mortar to the back of the stone when required.

Periodically lift a newly placed tile to confirm:

• Adequate mortar transfer
  
• Proper coverage
  
• Full support at edges and corners
  
• Absence of excessive voids
  
• Correct mortar thickness
  
• Acceptable alignment and surface plane
  

Press the tile into the mortar using controlled movement. Do not rely on grout to support unsupported tile edges or fill large voids beneath the stone.

Remove mortar from the face of the stone and grout joints while it is fresh. Dried mortar can be difficult to remove, and aggressive cleaning may damage the stone.

Follow the mortar manufacturer’s stated working time, temperature requirements and curing instructions.

Allow the setting material to cure for the required period before grouting. The appropriate grout depends on the stone finish, joint width, application and performance requirements.

Before grouting the entire installation:

1. Test the grout on unused material or an inconspicuous area.
   
2. Confirm that the grout does not scratch the stone.
   
3. Evaluate whether the grout pigment affects the stone’s color.
   
4. Determine whether a pre-grout sealer or grout-release treatment is needed.
   
5. Obtain approval of the finished appearance.
   

Highly polished, textured, porous or light-colored stone may require additional precautions. Dark or strongly pigmented grout can stain or visually alter some natural stones.

Do not allow grout haze or residue to dry on the stone. Clean the surface according to the grout manufacturer’s instructions without flooding the installation with excess water.

Movement and perimeter joints should remain free of rigid grout and be completed with an appropriate flexible sealant.

Sealer requirements vary by stone type, finish and application. An impregnating or penetrating sealer may help reduce the absorption of water, oil and staining substances, but it does not make natural stone stain-proof, waterproof or maintenance-free.

Depending on the stone and installation, sealing may be performed:

• Before grouting
  
• After grouting and curing
  
• Both before and after grouting
  
• Only after testing confirms the desired result
  

Always test the sealer on an unused piece or inconspicuous area. Confirm that it does not create an unwanted color change, surface film or uneven appearance.

Follow the sealer manufacturer’s coverage, ventilation, application and curing instructions. Remove excess sealer before it dries on the surface.

For additional guidance, visit our Stone Care & Maintenance page.

Protect the completed installation from foot traffic, water, impact, construction debris and premature cleaning for the full curing period required by the installation-material manufacturers.

Curing time may be affected by:

• Stone type
  
• Mortar and grout formulation
  
• Tile size and thickness
  
• Temperature and humidity
  
• Substrate and membrane type
  
• Interior or exterior conditions
  
• Moisture exposure
  

Do not cover a curing installation with materials that may trap moisture or transfer dyes to the stone unless approved by the installation-material manufacturer.

Do not place rugs, furniture, fixtures or heavy equipment on the surface until the complete installation system has adequately cured.

Natural stone can be used in many showers and wet areas when the selected stone and complete installation system are suitable for the application.

A wet-area installation requires more than water-resistant tile and grout. The substrate, waterproofing membrane, drains, penetrations, slopes, mortar, grout and flexible sealant must function together as a complete system.

Important considerations include:

• Properly sloped shower floors
  
• Continuous waterproofing
  
• Correctly treated seams and penetrations
  
• Compatible drain assemblies
  
• Appropriate mortar coverage
  
• Movement joints and flexible sealant
  
• Stone porosity and maintenance requirements
  
• Adequate ventilation and drying
  

Some stones may temporarily darken when wet or require more frequent maintenance in shower environments. Consult a qualified installer and the installation-system manufacturer before selecting natural stone for continuously wet applications.

Natural stone tile and grout are not substitutes for a properly designed waterproofing system.

Exterior installations are exposed to temperature changes, direct sunlight, rain, freeze–thaw conditions and substrate movement. The correct installation method depends on the stone, climate, substrate, drainage and applicable building requirements.

Exterior projects may require:

• Proper slope and drainage
  
• Freeze–thaw-suitable stone and installation materials
  
• Exterior-rated mortar, grout and membranes
  
• High mortar coverage
  
• Correctly designed movement joints
  
• Protection from moisture intrusion
  
• Specialized mechanical support for certain vertical applications
  
• Compliance with local building codes
  

Do not use an interior installation method outdoors without written confirmation that the complete system is approved for exterior use.

Natural stone pavers, pool coping, veneers and elevated installations may require methods that differ substantially from standard interior tile installations. Consult a qualified professional familiar with the project’s climate and application.

Order enough material to account for cuts, layout selection, natural variation and possible future repairs.

A general starting point is:

• 10% additional material for straightforward installations
  
• 15% or more for diagonal layouts, complex patterns, extensive cutting or highly selective blending
  

These percentages are general planning guidelines rather than fixed requirements. Your installer should calculate the final quantity based on the actual dimensions, tile size, pattern, layout and site conditions.

Because natural stone can vary between production lots, retaining extra material from the original order is recommended for future repairs or replacements.

Use our Tile Calculator to estimate the starting quantity for your project.

Once natural stone is installed, concerns involving color, variation, finish or layout become installation issues rather than unused-product issues. Inspect and approve all material before mortar is applied.

Natural variation should be blended intentionally. Installing directly from one carton at a time can create concentrated patches of color, shade or veining.

The wrong mortar can contribute to poor bonding, discoloration, moisture-related staining or deformation in sensitive natural stone.

An uneven substrate can create lippage, inadequate mortar coverage and an irregular finished surface.

Unsupported areas beneath the stone can increase the risk of cracking or hollow spots, particularly around tile edges and corners.

Grout color, aggregate and cleaning methods may scratch, stain or visually alter certain natural-stone finishes.

Required movement and perimeter joints should not be filled with rigid mortar or grout. Use an appropriate flexible sealant where movement accommodation is required.

Acidic or abrasive cleaners can etch, dull or discolor many natural stones, including marble, limestone, travertine and onyx.

Do not schedule demolition or installation based only on an estimated delivery date. Receive, inspect and approve the complete order before beginning time-sensitive project work.

Before Installation

• Confirm the product, size, finish and quantity.
  
• Inspect all cartons and document any concerns.
  
• Dry-lay and blend material from multiple cartons.
  
• Verify that sufficient additional material is available.
  
• Approve the layout and grout-joint width.
  
• Confirm substrate condition and flatness.
  
• Complete required waterproofing or crack isolation.
  
• Verify mortar, grout, membrane and sealer compatibility.
  
• Test grout and sealer on extra material.
  
• Review movement-joint requirements.
  

During Installation

• Follow all installation-product instructions.
  
• Maintain consistent mortar application.
  
• Apply mortar to the back of the stone when required.
  
• Periodically check mortar transfer and coverage.
  
• Keep grout joints clear of excess mortar.
  
• Clean the stone before residue dries.
  
• Protect movement and perimeter joints.
  
• Continue blending material throughout the installation.
  

After Installation

• Allow the complete installation system to cure.
  
• Protect the surface from traffic and construction activity.
  
• Apply sealer when appropriate.
  
• Use cleaning products approved for natural stone.
  
• Retain extra pieces for possible future repairs.
  
• Follow the installer’s maintenance recommendations.