If you're having porcelain tile installed and you're looking for confirmation or validation that the project will be completed correctly, where do you go?
The tile industry takes seriously its standard-setting role and its commitment to encouraging and supporting installer skill and knowledge. That's why the Tile Council of North America (TCNA), the National Tile Contractors Association (NTCA), the Ceramic Tile Distributors Association (CTDA) among others and the Ceramic Tile Education Foundation (CTEF) exist:
To provide guidelines, education and certification for correctly installing porcelain tile, always refer to these organizations for guidance.
Tile is beautiful, versatile, easily maintained, and it has a rich history. It is also a practical product which must be installed correctly.
It's helpful to know where to find installation resources so you can comprehensively evaluate your installer's skill and knowledge before he or she is hired to complete your dream installation.
ANSI and TCNA Handbook
Here are the primary tile industry standards, methods and guidelines used for the proper installation of ceramic, porcelain, glass, and stone tiles.
- American National Standards Institute (ANSI) A108 and A118 - American National Specifications for the Installation of Ceramic Tile - Material and Installation Standards
- ANSI A137.1 - American National Standard Specifications for Manufacturing Ceramic Tile
- Tile Council of North America (TCNA) Handbook for Ceramic, Glass, and Stone Tile Installation
These standards and guidelines are extensive in that they cover many types of installations using proven best practices, methods, techniques and materials recommended for a variety of structures and substructures.
For example, ANSI A108 defines the acceptable lippage (a condition where the edge of a tile is higher than that of an adjacent tile, giving the finished surface an uneven appearance) for installed Pressed Floor and Porcelain Tile that has been tested and passed the required minimum standards for ceramic tile (found in ANSI A137.1) as follows:
- All sizes of Pressed Floor and Porcelain Tiles with grout joint widths of 1/16” wide to less than 1/4” wide: Allowable lippage is 1/32”.
- All sizes of Pressed Floor and Porcelain Tiles with grout joint widths of 1/4” wide or greater: Allowable lippage is 1/16”.
For reference: 1/32” is roughly the thickness of a credit card. 1/16” is roughly the thickness of one penny.
NTCA Reference Manual
The National Tile Contractors Association produces the NTCA Reference Manual. It's an invaluable tool for the tile industry and a well-respected companion document to the TCNA Handbook for Ceramic, Glass and Stone Tile Installation and ANSI standards.
The Reference Manual is a comprehensive blend of the knowledge, experience, research, and development of the NTCA Technical Committee members, which includes ceramic tile contractors, consultants, distributors, manufacturers and others associated with the tile industry.
It's updated annually and includes close to 300 pages of information covering everything from substrate preparation to finished grout.
The purpose of the Reference Manual is to identify recurring tile and stone installation challenges, recognize potential problems, and gain consensus from industry experts on workable solutions to these challenges.
>> See NTCA Reference Manual: An Invaluable Tool for the Tile Industry
How to Use this information?
For quality-oriented tile contractors, these standards will be a guide for all of their ceramic tile installations. They are all available for purchase by the consumer, whether they be residential or commercial, and will provide direction relating to the best method available.
If you are an owner considering a project that includes tile, we strongly encourage you to interview and hire a qualified tile contractor who employs industry-recognized mechanics. Installers of this caliber own, understand, and use the tile industry standards listed above.

The most common sources of tile problems have to do with misunderstandings in expectations between the homeowner and the installer. They include the following:
1. Warpage
Warpage is particularly relevant with rectangular tile, aka planks. Today’s popular larger tile sizes can be 6” x 36”, 24" x 48" or larger and include an industry standard for an allowable amount of warpage (where the center of the tile is higher than the edges or ends). A qualified tile installer will know how to compensate for this inherent warpage, so any lippage is within this tile industry accepted tolerance.
>> See Do You Have Enough Mortar to Accommodate Most Tile Warpage?
2. Color/Texture Variation vs. Expectation
Shade variation can and does occur with ceramic and porcelain tiles. It can also happen as a result of new tile trends where designs purposely exhibit substantial variation in color and texture from tile to tile.
Be aware of this variation and view samples from current inventory when possible.
a. Research and educate yourself about shade variation
Consumers of tile products need to understand what shade variation is and how it can affect a tile installation. On the commercial side, this research many times is done by the architect or specifier. On the residential side, consumers, unless working with a designer, need to investigate tile shading which can be very subtle, while others vary widely.
b. Refer to a tile shade variation chart
Oftentimes, a visual on shade variation is worth a thousand words. Look for it and refer to it when making selection decisions.
Most sample boards or tile literature now list a range of shade, tone, texture and color as found in the TCNA Handbook and similarly in the ANSI A137.1 Specifications for Ceramic Tile.
This chart, as shown in Table 3 below, ranges from V0 (zero) which exhibits no shade range detectable by the average eye to the potentially extremely varied color and tone of a V4.

c. Be cautious of tile selections made from an image
Be especially cautious of making a tile selection from a color photo or image online. While being a great way to save time, there is nothing like seeing, touching, experiencing, and knowing all about the selection before the tile is ordered.
Additionally, a computer or tablet monitor may not be color perfect. There's no recourse once the tile is installed, except to remove it and start over.
d. Encourage customers to look at several pieces of tile
When consumers select tile without the assistance of a knowledgeable installer or salesperson to guide and counsel them on how the end result might look, problems can develop.
That is particularly true if the tile selection is based on a single piece of tile or from a small cut piece on a sample board. One single piece of tile cannot adequately represent the overall effect of a roomful of that tile installed. You can imagine how painful the results can be!
e. Insist on a mockup!
The safest way to eliminate surprises is for the installer to provide customers with a mounted and grouted panel that shows the tile shade variation, pattern layout (if the job calls for it), the size and color of the grout joint along with the sheen and texture of the color-coordinating sealant joints before the job begins.
When this is approved, the customer should sign and date the back of the mockup which offers proof that the entire spectrum of the tile job has their approval.
Installers may say that following this procedure will cost additional time and money, which it does, but this cost is minimal when compared to the cost of a possible tear out and replacement. Finding and fulfilling customers’ tile desires in advance will save a lot of headaches and money.
3. Large Format Tile
Tile sizes are increasing. As a result, tile installers must know how to accommodate inherent warpage associated with large format tile, as well as how to provide a surface that will allow these products to be installed without lippage or at least within the allowable tolerances provided in the ANSI documents.
>> See Is Your Floor or Wall Flat Enough for Large Format Tile?
4. Grout Joint Size
Depending on the type of tile, the pattern and the offset, the grout joint size may vary. So, what you want vs. what tile industry standards will allow, specifically ANSI A108.02 Section 4.3.8 regarding grout joint size, in relation to the tile size, dimensional precision, and offset pattern recommend, may not be possible (or desirable).
5. Visual Tile Defects
When tile is made, it goes through a comprehensive grading process to ensure that the end user is receiving the best quality product.
However, occasionally a blemished or defective tile may get through this process. Most tile manufacturers encourage installers to be the final inspector of tile quality as the tile is being set. Commonly, the box will provide messages to the installer such as:
“Tile setters: Check tile before setting. Claims cannot be accepted after installation”
Chapter 6: A Solution to These Problems: Mockups
For all of these situations, a mockup will anticipate the issue.
That's why it's critical to work with a Certified Tile Installer. Qualified labor will understand the importance of addressing these questions up front and ensuring that your expectations for the project are met. A mockup costs much less than ripping out an unacceptable job and redoing it, not to mention the costs associated with a lawsuit.
What is a Mockup?
Wikipedia defines a mockup as follows:
"In manufacturing and design, a mockup, or mock-up, is a scale of full-size model of a design or device, used for teaching, demonstration, design evaluation, promotion, and other purposes. Mock-ups are used by designers mainly to acquire feedback from users.
Mock-ups address the idea captured in a popular engineering one-liner: You can fix it now on the drafting board with an eraser or you can fix it later, on the construction site with a sledge hammer."
Mockups for Installing Tile Help Gain Owner and Specifier Approvals
How true that last sentence is, especially in today's fast-track world of construction. It's equally true for installing tile.
In the tile world, mockups should be used as a tool by the tile contractor to obtain the approval of the owner and possibly also the architect, designer and general contractor - all important specifier constituents for the end project.
Establishing how the finished tile installation will appear before the work begins is a wise choice which can save time and money.
Mockups Demonstrate Exactly What to Expect from a Tile Installation
Ultimately, the use of a mockup is a really good idea that can demonstrate to the end user, who may have difficulty visualizing the final finish, exactly what to expect.
The mockup shows the range of color and/or texture within the tile, the pattern or offset (if applicable), the size, texture and color of the grout joint, the appearance of the sealant joints, and any accessory items that will be used on the project. This way there are no surprises, unhappy customers or unfulfilled expectations upon completion of the project.
One special note on sealant joints –
Always educate yourself on the characteristics and appearance of sealant joints. Sealant joints, which are mandatory in all tile installations, will complement or coordinate with the grout color. Since the 100% silicone sealant is a different product and texture from the grout, using the word matching is not appropriate.
Finally, be certain to obtain the signatures of all interested persons including, the owner, architect, designer, decorator, and general contractor.
>> See Thin Tile Installation Expertise Creates Clubhouse Bar & Lounge where CTI Dan Welch describes how important detailed drawings were for executing the project correctly.

Chapter 7: How to Deal with Major Installation Problems
And then there's pure tile installation incompetence which leads to terrible horror stories. These horror stories are most times created by one of three causes:
- The “tile placer” (we can’t call him or her a tile installer due to almost complete lack of talent and knowledge) was not a Certified Tile Installer (CTI) through the Ceramic Tile Education Foundation (CTEF) and therefore not considered Qualified Labor,
- The job specifications did not clearly outline the scope of work including the installation methods, or
- The end user went with the lowest bid which could not provide the required quality or meet the finished installation expectations.
How Do You Deal with These Major Problems?
Depending on the type of issue you have, you'll want to start by contacting the installer. If you are working with a General Contractor, a remodeler or a retailer, find out who is paying the installer and contact that person.
If that conversation becomes difficult, your next option is to go to small claims court.
1. Contact an inspector for an independent third-party evaluation that will stand up in court. Get an assessment that includes an impartial determination of the situation.
Note: A third-party evaluation may cost between $2,500 to $3,500 per day + expenses.
2. For your visit to the small claims court judge, it's wise to hire a lawyer. Be aware that this process can take weeks to months depending on the judge's docket.
Note: If you have no written agreement or contract, the judge may not even hear your case.
You may have the option to go through arbitration whereby a 3-member panel reviews and decides on your case. But be advised, both parties must agree to a statement that the case can't be tried again or taken to a high court. The arbiter's decision is final.
Pay particular attention to working from a mockup before the project begins so you and your installer have agreed on the same expectations for the final outcome.
We've all seen it: that really ugly white powder that grows on cement grout and also tile, stone, brick and concrete, particularly when it's installed someplace with moisture (i.e., in a basement or outdoors). That white residue is called efflorescence.
What Causes Efflorescence?
Efflorescence for Inspectors explains that,
"Efflorescence (which means "to flower out" in French) is the dissolved salts deposited on the surface of a porous material (such as concrete or brick) that are visible after the evaporation of the water in which it was transported."
You might hear it referred to as "new building bloom" or even "whiskers."
According to the Portland Cement Association Trowel Tips information sheet of Efflorescence (downloadable PDF),
" A combination of three common circumstances creates efflorescence:
- soluble compounds (i.e., salts) in the masonry or adjoining materials
- moisture to pick up the compounds and carry them to the surface
- evaporation or hydrostatic pressure that causes the solution to move
If any one of these conditions is eliminated, efflorescence will not occur."
Efflorescence, then, happens. A professional tile installer can anticipate such situations to prevent it from occurring.

Figuring Out Why Efflorescence Happens
Tile installers are often called on to look at challenging installation opportunities and use their expertise to solve problems when they occur. Finding the solution can be difficult, and sometimes we scratch our heads and say, “Why is it doing that?”
Many times, installers are asked to install exterior tile on a job that appears to be elementary. Unfortunately, some of them develop issues at a later date.
Take for instance a job calling for a natural stone to be installed on the exterior wall of a new retail store which has a roof above it.
The plans call for the stone tile to be installed over a waterproofing membrane coating the cementitious backer board on steel studs. It sounds routine and it should function well; which it did in this case, for about a year.
Sometimes Efflorescence Isn't the Fault of the Tile Installation or the Installer
As time passed, the owner began to see a white powdery substance growing on the grout joints. Immediately the call goes out, “There is something wrong with the grout.”
Upon investigation, the grout had not failed, but a naturally occurring mineral salt which is present in all Portland cement products (thin set mortars and cement grouts) had found its way to the surface. This salt deposit is called efflorescence.
Normally, these residues can be washed away with a very mild acid solution and a bristle brush while being careful not to harm the stone (always test first to be certain the acid will not alter the existing finish). It this case it worked… for a little while. Continued scrubbing removed the salts, but it kept coming back. What was the cause?
For efflorescence to occur on the surface, water must be present to carry the minerals to the surface, evaporate and let the salts behind.
You may say, “It was the rain water going through the grout joints.”
The rain could have been the culprit, but not in this case. Remember, there was a roof over the tile.
The problem was actually caused by the roofer who failed to properly install the metal cap flashing on the parapet wall above the roof. The water went through the defective flashing, down through the thin set mortar to the lower portion of the wall and blossomed on the grout joints.
Once the tile installer (now a forensic specialist) found the problem, the roofer made the necessary repairs, the tile installer washed away the salt deposits and magically the efflorescence disappeared.
Understanding Efflorescence
In this example, defective roof flashing led to excessive moisture, which in turn caused that ugly white powder on the grout joints and tile.
In another situation, the problem could be the result of moisture from the soil under a basement floor or wall and might require a vapor migration membrane instead.
The important point is to find the source of the problem and solve it, so efflorescence doesn't reoccur. This is what identifies a true tile installation professional.
Are you a tile contractor? Do you have at least two years of experience as a full-time lead tile installer? By experience we mean that you have full responsibility for substrate prep, layout, along with properly installing underlayment, tile, grout and sealant materials. If yes, consider becoming a Certified Tile Installer (CTI).
The CTI program is the only third-party assessment of a tile installation professional’s skill and knowledge that is recognized by the tile industry. By taking the CTI tests, you validate your skills and knowledge; it truly sets you apart as a successful installer of tile.
Unlike other trades such as plumbing or electrical work, tile installation is an unregulated industry with no formalized training, testing or licensing requirements.
What that means is that a lot of tile is installed improperly. This becomes more of an issue as tile sizes trend larger and longer and installation materials become more technologically advanced. Furthermore, tiling a kitchen or a bathroom - or any room in the home for that matter - represents a major investment meant to last a long time. Ripping the job out is a big deal, not to mention a major inconvenience. Much better that the tile be installed properly the first time.
The best way to ensure that consumers have a choice when selecting a tile installer is to only consider someone who has successfully completed the Certified Tile Installer (CTI) program.

How Certification for Tile Installers Got Started
The Ceramic Tile Education Foundation (CTEF) launched the CTI program in 2008. The reason: to provide a means for good, knowledgeable tile contractors to verify their skills and promote themselves to potential clients and employers.
At the same time, the program addresses a significant opportunity in the marketplace:
- It provides consumers with a mechanism for identifying the level of proficiency of prospective tile installers. That's why this site includes a zip code locator for CTIs.
- That in turn encourages them to use only the best-qualified installers, ensuring that their tile projects are installed correctly from the beginning, and look beautiful for years to come.
The CTI program is a comprehensive testing of the skills and knowledge of experienced tile installers which includes an online, open-book multiple-choice exam along with a hands-on test based on current industry standards and best practices for producing a sound installation that exhibits good workmanship. The tests, therefore, require that both the observable and non-observable characteristics of a finished installation are executed properly.
The hands-on test in particular is difficult to pass; it requires true skill and experience. Many installers who have taken the hands-on test have said, “It is the toughest twenty-five feet you will ever install.”
Certification means that truly talented and qualified installers can compete against low-cost incompetent installation. This 9-minute video takes you through the hands-on test evaluation process.
The CTI program is administered by the Ceramic Tile Education Foundation at locations around the country. It is the only tile installation certification which is recognized by the entire tile industry based on the same parameters and performance standards established by the tile industry.
When someone successfully completes the program, you know that the Certified Tile Installer has passed a national standard on how to install tile. You know the job will be done properly the first time.
What are the Benefits of the Certified Tile Installer Program?
The Certified Tile Installer program benefits everyone! It really helps to have a higher level of quality installation professionals. Bad installations hurt every tile company and tile installer, not to mention the homeowner.
That's right. The end beneficiary of the Certified Tile Installer program is especially the end user - the homeowner or the building owner - who gets a stamp of approval that the tile installer has gone through an education process and represents the best quality labor possible.
It's important to be educated and trained to do the installation job per the standards and specifications and make it aesthetically pleasing for the end user.

Chapter 10: Next Steps
So, you're ready to hire a tile installer for that stone-glass mixed mosaic decorative border that will look perfect with the large format wall tile and wood plank floor tile you selected. What are your next steps?
Find a Certified Tile Installer
Here's the roadmap we've put together for you based on years of experience ensuring that tile gets installed correctly the first time because your tile installer is truly considered qualified labor.
Step 1. Make Use of this Guide to Select a Qualified Tile Installer
Use the information we've put together. Ensure you hire qualified labor.
>> See Looking to Hire a Tile Installer? Here's Your Roadmap.
Step 2. Find a Tile Setter Near You
>> Visit the CTI Zip code locator on this website to find a CTEF Certified Tile Installer.

Support the Mission of CTEF
We invite you to encourage dealers and distributors you know to work with Qualified Labor and promote Certified Tile Installers. All tile consumers, both residential and commercial, deserve to have their tile projects installed correctly and successfully the first time.
Have Questions?
Let us know if you have additional questions.
Have Suggestions or Additions?
Please let us know how we can improve the quality of this document.

Thank you for reading.
We hope this information has been helpful to you and your journey into the beautiful and long-lasting attributes of tile installed by Qualified Labor.
The CTEF Organization
Note: Banner images in this guide are courtesy of talented Certified Tile Installers whose work you can view in the Gallery of CTI Installations.
"... When you go into an estimate you must be armed with knowledge and have with you the proof of that knowledge. You must be licensed, certified, insured and have proof of that along with the literature that proves what you are trying to convey to your customer. You may be the only one explaining that it is necessary to install expansion joints however if you backup what you are explaining with the proper credentials and literature they will not only believe you, but you will get the job.
I leave a copy of my license, any certifications, and liability insurance with every estimate that I give. Also, if a customer would like references, I leave them a copy of every customer that I have confirmed with and explained to about this list with that new potential customer.
After you complete a job you ask the customer if they could be put on a referral list in which they could receive a call from a potential customer. Some people like their privacy and I respect that, however most people will agree to be on the list..."