• Sign In
  • Create Account
  • Sign Out
  • My Account
  • NEWS
  • PRODUCTS
  • A&D
  • INSTALLATION
  • MARKETS
  • AWARDS
  • EDUCATION
  • BUYER'S GUIDE
  • MEDIA
  • EMAGAZINE
  • SIGN UP
cart
facebook twitter linkedin youtube
  • NEWS
  • Breaking Flooring News
  • eNewsletters
  • PRODUCTS
  • Carpet & Area Rugs
  • Hardwood
  • Installation Products
  • Installation Tools & Equipment
  • Laminate
  • Resilient
  • Specialty
  • Tile & Stone
  • MARKETS
  • Commercial
  • Residential
  • AWARDS
  • Installation Awards
  • Top Flooring Products
  • EDUCATION
  • Continuing Education
  • Webinars
  • Sponsored Insights
  • MEDIA
  • FLOOR Podcast
  • Videos
  • TISE 2025 Videos
  • eBooks
  • EMAGAZINE
  • eMagazine
  • Archive Issues
  • Contact
  • Advertise
search
cart
facebook twitter linkedin youtube
  • Sign In
  • Create Account
  • Sign Out
  • My Account
  • NEWS
    • Breaking Flooring News
    • eNewsletters
  • PRODUCTS
    • Carpet & Area Rugs
    • Hardwood
    • Installation Products
    • Installation Tools & Equipment
    • Laminate
    • Resilient
    • Specialty
    • Tile & Stone
  • A&D
  • INSTALLATION
  • MARKETS
    • Commercial
    • Residential
  • AWARDS
    • Installation Awards
    • Top Flooring Products
  • EDUCATION
    • Continuing Education
    • Webinars
    • Sponsored Insights
  • BUYER'S GUIDE
  • MEDIA
    • FLOOR Podcast
    • Videos
    • TISE 2025 Videos
    • eBooks
  • EMAGAZINE
    • eMagazine
    • Archive Issues
    • Contact
    • Advertise
  • SIGN UP

Pro & Con: Ceramic Organic Mastics vs. Thinset Mortars

By Joe Grady
November 7, 2000
This tile installation failed because an improper installation of the backing was not detected before the tile was set.


TCA detail F113-2K outlines recommended uses for dry-set and latex-Portland cement mortar floor installations.
It’s not really fair to compare organic mastics to thinset mortars, because mastics occupy a particular niche in the industry and should be used only within very specific parameters. For example: for floor installations, organic mastics should only be used in residential applications. In contrast, thinset mortars can be used in commercial and residential environments.

Organic mastics are divided into two categories. “Type I” describes the most water-resistant mastics. These may be used in commercial and light-construction applications where there is some limited water exposure. Type I products also may be used for residential floors and countertops.

“Type II” mastics are restricted in terms of recommended use, because they do not have as high a level of water resistance as Type I products possess. Type II mastics may be used only for walls and ceilings in light-construction applications that are dry or subject to minimal water exposure.

At this point, it might be relevant to consider suitable applications for mastic use in light of ANSI 108 definitions:

Commercial construction (dry or limited water exposure) — dairies, breweries, commercial kitchens, laundries, etc.

Light construction (wet walls) — tub enclosures, showers and similar areas.

To illustrate the difference between Type I and Type II mastics, I’ll reference one important test: shear strength after water immersion. Type I products must meet a standard of 50 psi, whereas a Type II mastic is bound by a 20 psi requirement.

Dry-set mortars have strengths, expressed as “shear values,” that relate to the type of tile being installed. The values for seven-day water immersion testing are 150 psi for glazed wall tile, 100 psi for impervious tile and 50 psi for quarry tile.

Proper application of organic mastics for floor installations is covered in TCA detail F142-2K.
As you can see, the requirements for mastic and dry-set mortars vary widely. Because they are packed ready to use in cans and pails, mastics are preferable to many users. Dry-set mortars must be mixed with water on the job, which creates a more labor-intensive situation for the installer. However, as I mentioned before, the use of mastics is limited in scope and these limits must be strictly observed.

Mastics will not withstand high-impact or wheel loads. And in cases where on-grade concrete slabs are subject to a great deal of moisture intrusion via water vapor transmission, there is increased potential for bonding problems over time.

Another small but vital point is that mastics cannot withstand exposure to temperatures in excess of 140º F. You may be wondering where such conditions would be prevalent. I’ve seen failures where ceramic tile has been installed with mastic behind the ovens in pizza kitchens.

Organic mastics, which are water-based, should not be used for installation of natural marble. There are two reasons for this. First, the water content of the mastic can cause “curling” of marble, especially the black and green varieties. And second, impurities in the water/mastic can migrate upward and stain the marble (because marble is very porous).

A good many mastics are used today and, not surprisingly, a large percentage of tile is being installed with mastic. If you opt to follow suit, make sure to use the proper type (I or II), refuse to use any non-spec mastics and be sure that the job site conditions are appropriate.

Proper application of organic mastics for wall installations is covered in TCA detail W223-2K.

Dry-set mortar also has limitations. Tile Council of America (TCA) method F111 is preferred over precast and post-tensioned concrete floor systems, as well as other floors that are subject to movement of deflection. Any deflection should not exceed 1/360 for above-grade slabs.

As usual, I conclude with the advice that you observe all precautions and conform to applicable industry standards. Almost all of the failures I encounter are the result of some violation of the Standard of Care.

KEYWORDS: grouts and mortars

Share This Story

Looking for a reprint of this article?
From high-res PDFs to custom plaques, order your copy today!

Joe Grady, author of Ceramic & Stone Close-Up, is internationally respected for his floor covering expertise — particularly in the areas of adhesives, installation and moisture-related problems. During a career that spans more than 30 years, Joe has worked for the W.W. Henry Co. and A.Z. Bogert Co., and served on numerous industry committees. He currently works with Advanced Testing Services in Fullerton, CA, as an expert on flooring problems.

Recommended Content

JOIN TODAY
To unlock your recommendations.

Already have an account? Sign In

  • resilient flooring

    The 7 Types of Resilient Flooring

    The resilient flooring category is comprised of many...
    Resilient Flooring
    By: Resilient Floorcovering Institute
  • QuickDrain USA’s ShowerLine linear drain

    Tips for Curbless Shower Installation Using a Linear Drain

    Consider these four tips when planning for a curbless...
    Installation How-To
    By: Darryl Jones
  • 2024 New Flooring Product Guide

    2024 New Flooring Products Guide

    We explore this year's introductions in area rugs,...
    Commercial Flooring
    By: FLOOR Trends & Installation Editors
You must login or register in order to post a comment.

Report Abusive Comment

close

1 COMPLIMENTARY ARTICLE(S) LEFT

Loader

Already a Registered User? Sign in now.

Manage My Account
  • eMagazine
  • eNewsletter
  • Online Registration
  • Manage My Preferences
  • Subscription Customer Service

Retailers Share Top Takeaways from Shaw Flooring Network Convention

Retailers Share Top Takeaways from Shaw Flooring Network Convention

What Shaw Flooring Network Dealers are Banking on for 2025

What Shaw Flooring Network Dealers are Banking on for 2025

SolidTech R: Sustainable, High-Performance Flooring from Bottle to Floor

SolidTech R: Sustainable, High-Performance Flooring from Bottle to Floor

Shaw Flooring Network Retailers Report Post-Election Sales Surge

Shaw Flooring Network Retailers Report Post-Election Sales Surge

More Videos

Sponsored Content

Sponsored Content is a special paid section where industry companies provide high quality, objective, non-commercial content around topics of interest to the FLOOR Trends & Installation audience. All Sponsored Content is supplied by the advertising company and any opinions expressed in this article are those of the author and not necessarily reflect the views of FLOOR Trends & Installation or its parent company, BNP Media. Interested in participating in our Sponsored Content section? Contact your local rep!

close
  • Woodura Herringbone 2.0
    Sponsored byBjelin

    The Herringbone Floor of the Future

Popular Stories

company branding

Branding and Marketing Strategies for Flooring Contractors

Mimi Mulugeta and Michael Barrows

Military Vet Trades Retirement for New Flooring Venture in Alpharetta

how to properly trowel adhesive

Flooring Adhesives Education: The Key to Preventing Costly Installation Failures


Download the Free Moisture Meters Guide

Events

December 1, 2030

Webinar Sponsorship Information

For webinar sponsorship information, visit www.bnpevents.com/webinars or email webinars@bnpmedia.com.

View All Submit An Event

Poll

Growth Challenges in the Flooring Industry

What’s holding you back from growth in 2025?
View Results Poll Archive

Products

2025 BNI Interiors Square Foot Costbook

2025 BNI Interiors Square Foot Costbook

See More Products

FLOORtalk podcasts - Listen Now

×

We’re rolling out the red carpet of flooring knowledge!

Stay in the know on the latest flooring retail trends.

JOIN TODAY!
  • RESOURCES
    • Advertise
    • Contact Us
    • Directories
    • Store
    • Want More
  • SIGN UP TODAY
    • Create Account
    • eMagazine
    • eNewsletters
    • Customer Service
    • Manage Preferences
  • SERVICES
    • Marketing Services
    • Reprints
    • Market Research
    • List Rental
    • Survey/Respondent Access
  • STAY CONNECTED
    • LinkedIn
    • Facebook
    • Instagram
    • YouTube
    • X (Twitter)
  • PRIVACY
    • PRIVACY POLICY
    • TERMS & CONDITIONS
    • DO NOT SELL MY PERSONAL INFORMATION
    • PRIVACY REQUEST
    • ACCESSIBILITY

Copyright ©2025. All Rights Reserved BNP Media.

Design, CMS, Hosting & Web Development :: ePublishing

search
cart
facebook twitter linkedin youtube
  • Sign In
  • Create Account
  • Sign Out
  • My Account
  • NEWS
    • Breaking Flooring News
    • eNewsletters
  • PRODUCTS
    • Carpet & Area Rugs
    • Hardwood
    • Installation Products
    • Installation Tools & Equipment
    • Laminate
    • Resilient
    • Specialty
    • Tile & Stone
  • A&D
  • INSTALLATION
  • MARKETS
    • Commercial
    • Residential
  • AWARDS
    • Installation Awards
    • Top Flooring Products
  • EDUCATION
    • Continuing Education
    • Webinars
    • Sponsored Insights
  • BUYER'S GUIDE
  • MEDIA
    • FLOOR Podcast
    • Videos
    • TISE 2025 Videos
    • eBooks
  • EMAGAZINE
    • eMagazine
    • Archive Issues
    • Contact
    • Advertise
  • SIGN UP