What Mortar to Use for Backsplash

Choosing the right mortar for your backsplash project is an important decision that will affect the final look and durability of your backsplash installation. Here is a detailed guide on selecting the ideal mortar type for your specific backsplash needs.


A backsplash is a protective surface installed on the wall behind a sink, stove, or other area prone to water splashes and stains. Backsplashes are commonly made of tile, stone, glass, metal or other water-resistant materials.

Mortar is the adhesive material used to bind the backsplash tiles or sheets to the wall surface. Selecting the right type of mortar is crucial for proper adhesion and preventing cracks, loosening, and other failures over time. The mortar must be waterproof and able to withstand temperature changes, physical impacts, and shearing forces.

Factors to consider when choosing a backsplash mortar include:

  • Type of backsplash material
  • Environmental conditions
  • Type of wall surface
  • Desired final look and finish

With many mortar products available, it can be confusing to determine which is best for your particular backsplash installation. This guide covers the most common backsplash mortar types and recommendations for optimal use.

Commonly Used Mortars for Backsplashes

Cement Mortar

Cement mortar, also called thickset mortar, is a mixture of cement, sand, and water. It provides a strong bond and is water-resistant, making it a popular choice for backsplashes in kitchens and bathrooms. Cement mortar is suitable for use with ceramic, porcelain or natural stone tiles.

Best for: Most tile types, especially in wet areas like near sinks. Provides excellent adhesion.

Limitations: Rigid, not flexible. Unsuitable for fragile tiles prone to cracking.

Latex-Modified Mortar

This is cement mortar blended with a latex additive to increase its flexibility, adhesion and water resistance. The latex makes it more forgiving to work with and able to withstand shifting or cracks better than plain cement. It is suitable for indoor and outdoor use.

Best for: Most tile applications, especially extra protection in wet areas. Flexible bond for unstable tile materials.

Limitations: Costs more than regular cement mortar. Not ideal for stone tiles.

Epoxy Mortar

A two-part adhesive with epoxy resin and a hardener. Provides extremely strong, durable bonds between tiles and surfaces. Chemical and stain resistant. Long open time for positioning tiles. Often used for stone tile backsplashes.

Best for: Natural stone tiles, metals, glass. High durability and water resistance.

Limitations: Difficult to work with. Expensive. Toxic fumes.

Organic Adhesive

Made from organic materials like linseed oil, tree resins, carbohydrates or latex. Environmentally-friendly option suitable for ceramic and porcelain backsplash tiles. Flexible with good adhesion. Easy water clean up.

Best for: Eco-friendly option. Use on walls and countertops. Gentler than cement-based.

Limitations: Lower water resistance. Weaker bond strength.

Mastic Adhesive

Premixed tile adhesive made of a sticky mastic compound with fillers and resin. Convenient for small DIY projects. Just apply with a notched trowel. Has lower bond strength than mortars and limited water resistance.

Best for: Small backsplash projects, indoor dry areas only. Very easy to use.

Limitations: Not durable or water resistant. Temporary applications only.

How to Choose the Right Mortar

Consider the following factors when selecting an appropriate mortar for your specific backsplash:

Backsplash Material

  • Ceramic or porcelain – Cement or latex-modified mortar recommended. Ensure mortar meets ANSI specifications.
  • Natural stone – Epoxy provides best adhesion and accommodates stone movement.
  • Glass tiles – Epoxy for high bond strength. Latex-modified mortar also effective.
  • Metal tiles – Epoxy or latex-modified mortar.
  • Green or fragile tiles – Organic adhesive less likely to damage tiles.

Wall Surface

  • Drywall – Latex-modified mortar adheres well. Requires water-resistant drywall.
  • Concrete or plaster – Use cement-based mortar. May require primer for bonding.
  • Wood – Epoxy can bond strongly. Latex-modified also effective.
  • Existing tiles – Use epoxy thinset for best adhesion.

Environmental Conditions

  • Wet area – Epoxy or latex-modified mortar most water resistant.
  • High-traffic – Epoxy provides durable bond for frequent impacts.
  • Outdoors – Use latex-modified mortar resistant to temperature changes.

Desired Finish Look

  • Grouting – Cement mortar appropriate as base for grout lines.
  • Minimalist – Organic adhesive gives seamless look.
  • Bold patterns – Cement mortar allows precise tile alignments.

Always refer to manufacturer instructions for recommended uses and specifications for each mortar product. Some mortars require additional preparation like priming or modifications for certain finishes.

5 Key Tips for Mortaring a Backsplash

  1. Clean and prepare the wall surface – Remove old adhesive, dust, oils, and degrade any glossy paint.
  2. Select approved mortar for tile and wall type – Check manufacturer specifications for performance ratings.
  3. Mix to proper consistency – Mortar should hold shape but spread easily without drips or slumps.
  4. Apply even 1/4″ – 3/8″ layer with flat side of trowel. Back-butter large tiles.
  5. Beat tiles into place for maximum mortar contact before skins forms. Check for 100% coverage.

Frequently Asked Questions

What mortar should I use for a backsplash in the kitchen?

For kitchen backsplash areas which experience frequent water exposure, either cement or latex-modified mortar provides excellent adhesion and water resistance. Epoxy is also an option for maximum durability.

How do I mortar glass tile backsplash?

Glass tiles require a highly adhesive mortar able to accommodate their smooth surfaces. Epoxy thinset is ideal, providing a tenacious bond. Latex-modified mortar is also suitable for glass backsplashes.

Can I just use construction adhesive for backsplash tiles?

Construction adhesives lack the rigidity, durability and waterproofing needed for permanent backsplash installations. Mortar designed for tile provides a much stronger bond and resistance to damage.

What mortar should not be used for backsplash?

Mastic adhesives are not suitable for backsplashes as they lack long-term bonding power and water resistance. Organic mortars also have lower performance for wet areas subject to splashes.

How long does mortar take to cure for backsplash?

Curing time varies by product, but cement-based mortars generally reach full cure strength in 7-28 days. Epoxy cures more quickly in 1-3 days. Prevent water contact until fully cured.


Mortaring a backsplash requires selecting the appropriate adhesive for your specific tile material, wall type, and environmental needs. Cement-based and epoxy mortars provide the strongest bonds for most permanent installations. Be sure to follow manufacturer guidelines and proper application techniques for long-lasting results. The right mortar choice ensures your backsplash remains safely adhered and resistant to moisture for years of beauty and protection.