August 5, 2015

Thin Tile – July 2015

mapei_sponsorRetail rebirth in Ottawa

Architects and technicians use Neolith large thin tile to transform outdated department store into a sophisticated Nordstrom retail location

1-thin-0715Elegant. Light. Warm. When thinking of the Nordstrom brand, very specific descriptors emerge that evoke the chic, high-end style of the upscale retailer. Following a 2012 announcement that the former Sears location at Ottawa’s Rideau Centre would be reinvented as Nordstrom to anchor the $360 million modernization and expansion of the center, a great deal of care was taken to select architects, technicians and consultants that understood the brand, the vision and the goal. As the number-one retail design firm in the world – designing more than 150 new and remodeled Nordstrom stores in North America – Seattle-based architecture firm Callison was selected for the project in this high-traffic location in the heart of Canada’s capital.

2-thin-0715Callison ( began planning, digging deep into the design process and creating what would be an epic, dramatic revamp of 14,000 sq. ft. of dreary, worn exterior and interior storefronts. The completed elevations were sleek and specific, designed with large thin tile in a bright, gleaming white with subtle polished accents that would never stain, fade or discolor. The exterior façade would need to overcome the often harsh weather conditions in Ottawa, where temperatures of -20 degrees Celsius are common. An installation system that held tile firmly in place without grout lines was another necessity to carry out the team’s full vision. Callison realized this was a tall order.


With several key “must-haves” for the project, Callison began looking into potential solutions that would not sacrifice the design details that were so important to the overall aesthetic. After looking at a variety of surfacing materials, Callison was drawn to Neolith by TheSize (, a sintered compact surfacing product – that utilizes clays and other components – already used frequently in Europe for commercial façades. The product had a reputation for being incredibly durable and resistant to scratching, fading, staining and extreme temperatures. After meeting with Travis Conrad, architectural consultant for Neolith (, Callison’s team was feeling confident for the first time that their vision might become reality.

4-thin-0715“As architects, we definitely thought about design and the aesthetics of the project foremost, but design visions don’t often link directly to a functional solution, especially when looking at a high-traffic commercial project like the Nordstrom at Rideau Centre,” said Michael Lee, principal, Callison. “The product addressed our concerns from a design perspective – an array of tile colors to create patterns of horizontal movement, limited grout lines, varying panel heights and lengths to further reinforce the random nature of the façade, allowing for lasting warm colors – but also from a functional perspective in terms of durability.”

Neolith’s unique manufacturing process, which uses high pressure and high temperature to create a compact, nonporous surface, enables the product to withstand harsh conditions and emerge unscathed. A key concern for this project related to weather, as many compact materials are unable to withstand the coefficient of linear expansion in Ottawa, or the extreme fluctuations in temperature. Neolith’s design and use of 6”, 8” and 18” wide 6mm slabs in 5’ and 10’ lengths – in tandem with the unique Ceramitex mechanical installation system – provided a secure way to fasten the product without fear of cracking or splintering.

5-thin-0715Neolith and the accompanying installation system also provided several design benefits to the project. The exterior storefront has several sharp angles and edges, as result of the façade being raised away from the main structure. Using Neolith, a chamfer miter is possible, allowing for seamless L-shaped pieces for cladding the outside corners. This simplifies installation, improves overall aesthetic and avoids the use of unsightly vertical lines where sealing caulk often gets dirty and discolored. This project utilized both 90- and 135-degree miters, giving the building an effortlessly seamless appearance installed by Ontario Panelization, based in London, Ontario, Canada.

Aside from a clean, smooth look, the architects were also searching for specific colors. To contrast with the concrete and stone buildings surrounding the area, the façade was to be mostly bright white in matte and polished finishes with tan and grey accents. The team selected the pure Arctic White color in a satin finish as the base and accented that with scattered tiles of Barro, Perla and Arena in satin and polished finishes to round out the color scheme, supplied by Innovation Surfaces in Santa Ana, Calif. Neolith’s portfolio of nearly 50 colors and four finishes gave the team a vast amount of aesthetic freedom to get the design just right.

“Once my team [at Neolith] learned about the design goals and confirmed that functionality wouldn’t be an issue, you could see the architect team breathe a complete sigh of relief,” said Travis Conrad, architectural consultant, TheSize Surfaces. “We were happy to be able to offer a product and system that evenly matched the high-end quality of the Rideau Centre, Nordstrom and Callison, and let the architectural team focus on crafting a truly beautiful space.”

Qualified Labor – July 2015 – Collins Tile and Stone

Steve Keator, Collins Tile and Stone

CTI supports best practices; boosts client trust, installer confidence and marketability

1_CTI_20x20By Terryn Rutford, Social Structure Marketing

Steve Keator, director of Field Operations for Collins Tile and Stone in Ashburn, Va., can’t say enough about the value of being a Certified Tile Installer (CTI) affords his customers.

steve_keator“As a CTI, the work that I produce satisfies the greatest expectations and quality of work within the industry,” said Keator. “We establish trust and confidence with our clients when they know that our skilled CTIs are capable of performing all work using industry best practices and techniques resulting in superior quality and lasting installations.”

Having CTIs on staff makes Keator’s job easier. “I am responsible for maintaining a level of quality control over the tile installations by making sure that industry best practices and techniques are performed within each kitchen and bathroom remodeling project,” he said. “This task is easier for me because all of our tile mechanics are CTI certified.”

collins_logoCollins Tile and Stone leverages the CTI credentials of its employees in all its marketing. “We promote CTI credentials and post the CTI logo throughout our marketing materials, including our website, social media outlets (FB, Houzz, Pinterest), Angie’s List, and in the email signature of all employees,” Keator said. The company also designates that it is a company that employs CTIs on each business card.

“We promote the CTI logo on our company vehicles as well,” Keator said. “In addition, we cite CTI certification of our installers on every proposal and contract we provide to our clients to establish the high level of expertise of our tile installers.”

Keator took the CTI evaluation in November 2010 at Daltile in Richmond, Va. He took the written test in person and found finishing the hands-on portion in the allotted six hours to be the hardest part. Keator was grateful for his existing level of technical knowledge and the written test reinforced the necessity of industry methods and standards for producing top-quality installations.

And although the CTI evaluation is not a training course, Keator said, “[I] gained a greater understanding of the necessity of pre-sloping and proper weep hole protection, proper mud pan installation, different types of joist systems, and substrates and their requirements.”

After installing tile for five years, Keator, pursued CTI certification to advance his education and to increase his skills as a tile tradesman. All of this prepared him for a supervisory position.

Why should someone become a CTI? “Being a CTI sets me apart from other tile mechanics in the industry,” Keator said. “As a CTI, my skill level is proven and I know I am capable of building quality tile installations that will last. This has helped me to personally take pride in my work, as well as to build my career from an installer to a supervisor. I am more marketable with these [proven] skills and provide value to every job I complete.”

In addition to increasing the marketability of Keator and his employing company, he said that being a CTI has instilled an increased level of confidence in his installers and himself. “I am using industry best practices and techniques,” he said. “The fact that our company employs CTIs equates to a highly skilled [and] educated workforce.”

Keator has advice for installers thinking about becoming a CTI: be prepared. “Although the [written exam] was open book, I had to be fully prepared and well versed in tile installation technique and knowledge,” he said. Since “the manuals are rather large and comprehensive, it was imperative that I came prepared for the exam and was familiar with the information in order to locate references quickly, as needed, throughout the test.”

Tech Talk – July 2015

TEC-sponsorBuilding the perfect shower

By Lesley Goddin

Installing showers are one of the most frequent jobs encountered by a tile setter – and one of the most challenging. Managing water issues imparts another dimension to the USUAL demands of tile installation projects. In this edition of Tech Talk, we connect with some tile contractors who are experts at shower installations to learn about pitfalls of these projects and how to overcome them with beautiful results.

Top challenges

John Cox, owner of NTCA Five Star Contractor company Cox Tile in San Antonio, Texas, noted that logistics – especially getting materials to higher floors – take some planning. “Most residences do not have elevators, so scaffolding and ladders are the only means of getting materials to the bathroom.”

1-tt-0715Weather also is a contender for “muddying up” bathroom installs. That’s because to achieve the stunning bathroom effects it produces, Cox Tile muds its walls using the one-coat method, which is made all the more difficult when weather conditions are wet and humidity is high.

Both Cox and Buck Collins of Five Star Contractor Collins Tile and Stone in Ashburn, Va., cite walls that are neither plumb nor square as being problems on the job. Collins says this challenge is exacerbated by today’s use of “large-format tiles, seats and recessed niches,” and attacks the problem by plumbing the walls before rebuilding them. Cox added that his company is “exerting more labor and energy correcting workmanship issues,” such as lack of skilled labor and costs to create a plumb and square canvas on which to install tile. “We have to use a scratch and brown coat to our walls due to the depth when they are out of plumb or out of square,” Cox said.

When working with walls that need flattening, Joe Kerber, owner of Five Star Contractor Kerber Tile, Marble & Stone, Inc. from Shakopee, Minn., said that 1/16” sheetrock furring strips, available at big box home centers, can be used to fur out walls that are not flat or straight. He insisted, “Make sure that the walls you are going to set tile on are flat, not necessarily plumb.”

Kerber also noted that pitch to the drain can be a challenge when working with barrier-free showers. (see Kerber’s By the Book article on curbless showers in this issue.) “Sometimes we have to reframe the floor system to accommodate the correct pitch for the particular room,” he said.

Another issue that comes with shower installs is seats that are prone to leaking, Collins said. To alleviate this problem, Collins uses “pre-formed seats and niches to elevate any potential issues.”

Martin Brookes, owner of Five Star Contractor Heritage Marble & Tile, Inc., in Mill Valley, Calif., shared that his company has discovered that sometimes showers “will be redesigned after bid stage to a steam room without the owners being aware of the significant up charge and design changes to accommodate this scenario.”


Top tips for shower installs

Much of the wisdom around shower installs centers on waterproofing – clearly a key component to any successful shower or steam room project.

Cox recommended that contractors, “Understand and know the value in waterproofing. Especially niches, benches, seats, jambs and window frames. These are long-term problematic areas that do not get treated properly. They show up later down the line and are generally costly problems to correct.” Brookes declared that “Waterproofing the shower enclosure and shower pan is key in longevity of the shower stall. It’s critical to identify ahead of time if you need a trench drain instead of a traditional shower drain. Not every application will allow for the use of a trench drain with a barrier-free walk-in type shower stall. Sometimes the floor will need to be re-engineered to accommodate this application. Steam room applications will require a whole different approach and a different set of specifications to make it fully functional.” And be sure you “have proper pitch to the drain on all horizontal surfaces,” Kerber said.


Brookes confirmed, “The importance of waterproofing all niches and penetrations should be understood. All mounted accessories should be considered, and appropriate backing installed before preparation work begins. Follow the rules and understand the waterproofing requirements and your installation will survive for many years to come.” Brookes underscored the importance of reading and clearly understanding TCNA standards, as well.

Kerber pointed out, “Use correct installation procedures for your waterproofing. Remember, it’s not just waterproofing, its water management.” He also emphasized that contractors “get a good layout of the tile selections on all the walls, whether it is only two or as many as nine – as is the case of a shower we are working on right now. Sometimes this process takes time, practice, patience, and wisdom.” Kerber stressed using mortar or thinset to install tile. “Absolutely no acrylic adhesives in a shower,” he said. And use “premium grouts and caulks. No acrylic caulk at the shower floor.”

4-tt-0715Another essential is proper installation of shower pans, Cox said. “Understand that a shower is a working assembly,” he explained. “Pre-slope is critical, folding your corners, wrapping your curbs, and putting the proper corners on where needed. We build ours with bricks or blocks for long term. Also know that any curb built with wood cannot have any fasteners on the top or inside that will lead to water intrusion.”

And above all, before even starting, “Educate the builder and framer on how it affects your labor when they do not pay attention to their quality control,” Cox concluded.

Business Tip – July 2015


Benefits of international trade in the tile industry

CTDA members take a trade mission to Turkey
Contributed by CTDA staff

Thirty-four CTDA members recently traveled to Istanbul, Turkey, for an amazing experience they will never forget. The CTDA Trade Mission to Turkey gave members an opportunity to meet with Turkish manufacturers face to face, explore new trends in Turkish tile, visit showrooms, and network with each other. As the United States’ economy recovers and business in the tile industry picks up, distributors are looking abroad for the next great opportunity in tile. International business across all sectors has grown tremendously with advances in technology and a willingness to create a strong global economy.

Dr. Robert Mousettis, professor of International Business & Strategy, and coordinator of the Masters of International Business Program at North Central College in Naperville, Ill., explains that global markets are one of the most attractive reasons to conduct business with a world-wide view in mind.

BT-ctda-0715“In general, the international markets provide an opportunity to venture into untapped markets with enormous potential,” Dr. Mousettis said. “However, it is not easy; if it was, everyone would do it. It requires companies to be comfortable with complexity and ambiguity. It requires companies to have individuals who have exceptional intercultural skills, natural curiosity, flexibility, adaptability, and superb leadership skills.”

With major manufacturers all over the globe, distributors realize the importance of broadening their horizons to buy and sell products abroad. International business does not come without challenges. Dr. Mousettis cites differences in culture and politics as major obstacles to conducting business abroad. As CTDA members learned during the trade mission, understanding more about different suppliers by experiencing their culture first hand is one way to alleviate concerns and become culturally sensitive. Politics and legal differences can arise while doing business internationally so it is important to have a strong understanding and clear communication with business partners.

Imports increase Americans’ purchasing power and give them access to products that may not be available in the United States. The tile industry is full of opportunity for collaboration between countries that excel in creating quality materials demanded by educated consumers. International trade in the industry can also broaden distributor and retailer horizons on how to display, use and promote tile in local markets.

To learn more about the CTDA Trade Mission to Turkey, please visit the CTDA blog (

Ask the Experts – July 2015


I have a new construction (2008) post-tensioned slab where very small cracks have developed in my travertine tile flooring (ground floor). I had a contractor come out and he said that the standards recommend installing a slip sheet before applying the tile. Is there a professional article that I can use to back up my assertions to the original tile contractor that there should have been a slip sheet?


Since your installation was done in 2008, that year’s industry standards must be consulted. The 2008 TCNA Handbook for Ceramic, Glass and Stone Tile Installation states in method F113-07 in the Limitations section that “Method F111 is the preferred method over precast concrete floor systems, post-tensioned concrete floor systems and other floors subject to movement or deflection.”

Method F111 is an unbonded (includes cleavage membrane) wire-reinforced mortar bed, minimum 1-1/4” and maximum 2” thick. Hope this helps.

Michael Whistler, NTCA presenter


Could you direct me to a simple method to calculate the regulated flexural strength of cementitious floor tiles (i.e. equation or formula) for various areas of application (i.e. residential use vs. commercial use vs. industrial use)? There must be an ASTM standard for these floor coverings and a simple way to determine these flexural strengths depending on the length/width/thickness of the tiles. European standards use EN 14411 with the following formula: Breaking force F(N) = 2 x ß x h² x b /3 x L in which:

1. ß is flexural tensile strength of the tile (N/mm2)

2. h is tile thickness in mm

3. b is tile width in mm

4. L is tile length in mm

Thank you for the time that you will allocate to this information request.


There is no standard for cement floor tile, though there have been discussions over the years.

Relative to your question about flexural value, the U.S. does not address that issue in ceramic tile well. In addition to EN 14411, there is EN 14617 for agglomerated stone. I have found the 14617 standards of greater value when considering cementitious floor tile, primarily in the area of dimensional stability. On flexural value, architects typically put the cementitious tile in section 09300 and treat it as floor tile. When I get a claim on cement tile, one of the tests I often use is ISO 10545-4 because it has a standard for flexural value for ceramic tile. While ceramic is >30 N/mm2 and porcelain is 35 N/mm2, I often find cement tile anywhere from 10 to 17 N/mm2. This requires a surface with less curvature than a conventional tile to be successful. I have had well over a dozen large claims on cementitious floor tile. In the majority of them this was an issue and the dimensional stability was a problem as well.

David M. Gobis CTC CSI, Ceramic Tile Consultant

TCNA Handbook: new methods for curbless showers


joe_kerber“They just don’t build them like they used to.”

You’ve all heard that before, and most of the time that’s a good thing.

With our never-ending desire to have the “latest and greatest,” or the “biggest and best,” we continue to develop new ideas and challenge ourselves to help meet our customer’s wants and needs. Some of these ideas are thinner floor systems, and larger, curbless showers. Our manufacturing partners in the tile industry have been developing new products over the years to help us make this all happen.

There are three products that stand out in my mind as great inventions that have really advanced the tile industry: cement backer units, thin-set mortars, and today’s subject, topical waterproofing.

I was first introduced to topical waterproofing in the 1970s. I remember the old guys at the time saying, “What the hell is that crap?” Being the forward thinker that I am, I would say, “I’m going to try this stuff.” So I did. My wife Wendi and I were just starting to build our first new house. The building inspector at the time was an acquaintance of mine and when I approached him with the idea of a tiled tub in my house he said, “It’s your house, go ahead.” So we did. The many tiled tubs from that era are still in service today. I have been using topical waterproofing ever since. It is the one product that has really changed our design criteria.

Next challenge: if we can slope enough floor space on a bath floor so that the water from a shower runs toward a drain, do we need a curb? The answer is no. The issue that we had is that according to the IPC (International Plumbing Code) there had to be a “dam” outside the shower area in order to contain the water. However, in an ADA-compliant shower there is no dam or curb so the actual code does not apply. When talking with plumbing inspectors they agreed that a curb was not necessary as long as the water ran to the drain and did not affect any of the other surfaces. That is just “common sense.”

Let’s say you are ready to start a tile project that you were awarded. It has several ADA showers. You know the floors have to have a specific slope to the drain in the shower compartment area. You get there and find that the plumber has the drain too high or the concrete company has not placed the concrete correctly, or both. Now you have an issue with the pitch of the floor to the drain. What do you do?

You look at the tool that GCs, architects, lawyers and judges consult for answers to tile issues: the TCNA Handbook for Ceramic, Glass and Stone Tile Installation. It has many methods for showers that give you all the criteria and information for proven installation methods.

But wait – as of 2014 there was no method for a curbless shower! So we needed to develop one.

This should be easy, right? Let’s just take an existing proven method from the Handbook and expand on it. We’ll remove the curb and waterproof the bath floor area. We will then get a consensus from the Methods and Standards Committee so that we can move this method forward.


The plumbing inspectors will not approve this method for our members without a curb because of the code about the dam. But wait: tile installers have been building curbless showers successfully for quite a while, and inspectors are approving these installations, so let’s push forward. After some changes, the Methods and Standards Committee gives its blessing on this method, so now it has to go to the TCNA Handbook Committee. Here the Handbook Committee – made up of tile installers, manufacturers, consultants, expert witnesses, and people in the know – have the task of making changes and either approving or disapproving the method.

B421CFinally, in the 2015 Handbook, after about three years of work, there are approved methods for curbless showers, and you have information to show your GC how those showers need to be constructed before it’s too late.

It is a long, tedious and sometimes frustrating process to develop a new method in the Handbook. But it is well worth it because of the information it gives the tile installer.

I hope that everyone has a new TCNA Handbook and uses it. It has been developed for you, the tile installer.


kerber_showerJoe Kerber is president/CEO and co-owner with wife Wendi of Kerber Tile, Marble & Stone, Inc., in Shakopee, Mn. Kerber has been in the tile industry since 1969, and began his business in 1973. He has served as president and chairman of the board for the Independent Ceramic Tile Contractors Association (ICTCA), renamed CASTA (Ceramic and Stone Trade Association), and he is a member of the NTCA board, serving on the NTCA Technical Committee and Methods and Standards Committee. Kerber also is regional director for NTCA, which encompasses seven states. Kerber Tile, Marble & Stone, Inc. is a NTCA Five-Star Contractor, and employs CTEF Certified Tile Installers. Kerber was awarded a NTCA Best Practices award at Coverings in April 2015 for his Barrier-Free Shower Installation method, which is included in the 2015 TCNA Handbook for Ceramic, Glass and Stone Tile Installation.

Qualified Labor – June 2015

1_CTI_20x20The ACT exam: a life-changing experience for Mark Iosue of Mi Terra Custom Interiors 

By Terryn Rutford, Social Structure Marketing

Mark Iosue of Mi Terra Custom Interiors ( hung up his work boots a few years ago in favor of running his own installation shop, but last year he dusted them off to complete the Advanced Certification for Tile Installers (ACT) at Schluter Systems in Plattsburg, N.Y.

“I’m always trying to step up my game and become the best at what I do,” said Iosue. He has eight full-time and four part-time tile installers working out of two shops, one in Philadelphia and one in South Jersey.

Iosue is getting as many of his installers to take the Certified Tile Installer certification as he can. “I’m the only one who’s ACT certified,” said Iosue, but, “I really truly believe in it. If you’re certified, you walk into a job [and] you’re a lot more confident, you have a lot more experience than the next guy. If you passed that course you basically know what you’re doing.”

Iosue has been a tile installer for 20 years and started Mi Terra Custom Interiors 10 years ago, but Iosue described the ACT test as a life-altering experience. The ACT written and hands-on tests are not a training course, but Iosue still learned a whole lot. “I can’t say enough about the test,” he explained. “It was a life-changing experience for me for the simple fact [that] I learned so much from it. I got to meet a lot of great people, people like myself with the same goal to do the right thing when it comes to tile installations.”

Iosue raved about the test, but that doesn’t mean it was smooth setting. “I’d be lying if I said it was easy,” Iosue said. “Just because you’ve been doing it your whole life doesn’t mean you’ve been doing it right your whole life.”

According to Iosue, the hardest part was getting back into the actual physical work. “I mostly oversee things,” said Iosue. “I actually had to get the tools out. It’s been years since I’ve actually set tile. Plus, things were timed and I don’t have a young back anymore.”

Despite the challenges, Iosue believes it was worth it. “I thought it was very helpful, very beneficial. It made me a better tile setter.” Since becoming CTI- and ACT-certified, Iosue uses the TCNA Handbook more often. He investigates things a lot further, “basically doing my homework,” said Iosue. And all of this, he says, has absolutely, 100% positively affected his bottom line.

Iosue strongly advises tile installers to become CTI- and ACT-certified. “To be the best, you want to always test yourself and learn the most you can with your craft,” he said. “That’s what this test does. Even if you’ve been doing it for many years, there’s always something you can learn,” he said. “I recommend the test for anyone who does this for a living because it covers all bases. And once you take it you become qualified.”

Tech Talk – June 2015


Hot Weather Tiling

2014/2015 NTCA Reference Manual

Since summer begins this month, we are literally taking a page (or two) from the 2014/2015 NTCA Reference Manual that relates to hot weather tiling. Materials require special handling to reduce the individual or combined effects of high temperature, low relative humidity, and high winds.

For instance, portland cement mortars and grouts can require additional water or latex for mixing, which can affect the bond and result in less open time, higher incidence of skinning over, plus dry-shrinkage cracking and improper curing.

In hot weather, organic adhesives produce creamier textures and increased workability that may lead to troweling too large an area before applying tile, as well as faster skinning over. Hot weather can sometimes reduce the viscosities of epoxies, making them more workable and at the same time accelerating the rate of cure, which can wreak havoc with mixing equipment and leave an epoxy film on the tile that’s very difficult to remove.

What follows are recommendations from pages 140-141 in the 2014/2015 NTCA Reference Manual that support well-performing installations by minimizing or controlling conditions that result from hot weather for projects that must be executed in hot weather conditions due to budgetary and scheduling demands.

Be sure to consider each project individually, since following one recommendation may not be sufficient to rule out problems. Evaluate exterior installation sites in advance, observing how many hours a day the installation will be exposed to direct sunlight and winds, and whether it’s feasible to construct a temporary shelter that can be moved as work progresses or if the work is better done at night or a cooler time of day.

In addition to temperature of materials, you must monitor temperatures of the job substrate. Hot substrates will exacerbate the hot weather effects of skinning over, reduced workability, premature drying and inability to form a strong bond for cementitious grouts and mortars. If you choose to cool a substrate with water, be sure to remove all excess water before applying the mortar.


Keep all materials in a shaded area and do not store materials in closed trucks or vans. This includes tiles, mixing liquid, setting and grout materials. If any material is warm to the touch it is suspect.

Don’t use tile that is hot to the touch. Cool your materials before proceeding. Some manufacturers market products specifically developed for hot weather conditions. They can be consulted concerning their products’ performance and recommendations under specific job conditions.


Portland cement

mortars and grouts

If using water, fill buckets and put them in a shaded area. If possible, use a combination of ice and water. Mixing water has the greatest effect per unit weight of any of the ingredients on the temperature of a cementitious mortar or grout. It has a specific heat* between four or five times that of cement or aggregate. Thus a change in water temperature of about 4 degrees Fahrenheit can effect a 1 degree Fahrenheit change on a mortar or grout. By using ice water, a more dramatic temperature change can be effected. The use of cold water will result in a decreased water demand of the mortar or grout when mixing. The working time of the mortar or grout will be increased and the workability will be improved. Using warm or hot water will cause an increase in water demand, consequent decrease in performance, a rapid loss of workability and decreased pot life. An analogous situation exists for latex additives. Except here, the addition of ice to the latex admixture is not recommended. A better recommendation would be placing the latex admixture containers into an ice chest filled with crushed ice. The containers can then be removed and the pre-cooled latex used as needed. Before applying dry-set or latex modified portland cement mortars to concrete substrates, dampen the concrete to cool it down slightly. Control how much mortar is troweled and combed before setting the tile. High temperatures and wind can combine or skin a mortar in several minutes. Check for mortar transfer to the tile backs often as the installation proceeds. Scrape off and discard skinned mortar and apply fresh material whenever skinning is noted. Never re-temper or add additional liquid to a mortar or grout that has lost its workability. Begin damp curing installations involving unmodified cementitious materials as soon as it is practical.

Rapid water loss can result in dry-shrinkage cracking that will compromise the integrity of the installation and ruin an otherwise acceptable grout application.


Organic adhesives

The viscosity of organic adhesives decreases with higher temperatures, making it easier to spread and trowel. Avoid the tendency to spread too large an area before tiling. In higher temperatures and in the presence of drafts, organic adhesives skin over rapidly, preventing good transfer of adhesive to the tile being installed. Check transfer often by removing a tile and observing the amount of adhesive on the tile back. Cooling the adhesive will help somewhat, but cooling in an ice bath is not recommended since the workability of the adhesive will be adversely effected by the increased viscosity.


Epoxy mortars and grouts

Every effort possible should be made to keep the temperature of the epoxy, tile and substrate below 90 degrees Fahrenheit. This may require working at night, the use of ice baths to cool the mixed epoxy and control its rate of setting or the application of damp blankets or towels to the installed tile before grouting in an effort to cool them. Do not overmix the epoxy mortars or grouts. Do not pre-moisten concrete substrates before applying epoxies. All manufacturers of those materials require that the components be intimately mixed for optimum performance. This can be observed as a homogeneous lump-free mix or by a thorough wetting of the aggregate or by uniform color. When any of these conditions is observed, STOP MIXING! Excessive mixing will accelerate the rate of cure still further from the heat generated by the mixing action.

When grouting, do not attempt to grout large areas of the tile field before cleanup. The result can be an extremely difficult-to-remove cured epoxy film on the tiles.


*Specific Heat – The ratio of the heat capacity of a substance to the heat capacity of water, or the quantity of heat required for a I degree temperature change in a unit weight of a material. Commonly expressed in Btu/lb/degree F or in Cal/g/degree F.

Coming this summer – the second annual issue of TileLetter TECH! Learn about hot topics in the current NTCA 2014/2015 Reference Manual and changes coming to the 2015/2016 edition.

Business Tip – June 2015


NTCA makes apprenticeship and career development a top priority with web-based Learning Management System

By Dan Welch, Welch Tile & Marble, NTCA Apprenticeship Committee chairperson (Ed. note: This article is a follow-up to the story about the expansion of NTCA educational efforts with CEFGA and MiCareer Quest as reported in May TileLetter’s Benefits Box section. That May story introduced the idea of a Career Development Matrix, which is explained in greater detail here.) The daunting task of updating the existing NTCA apprenticeship manuals and transferring the information to a web-based Learning Management System (LMS) is under way. This Apprenticeship Committee began in San Antonio, Texas, at Total Solutions Plus where I again opened my mouth during a Training and Education Committee meeting and found out that this thought was a common concern and needed a chairperson. As the newly-appointed chairperson I set out to find an easy way to transfer information from the elder employees to the new millennials. BT_matrix_0615A Career Development Matrix idea was spawned during a post company-meeting event. The basic idea was to build a path easily understandable to the young men and women in our trade, linking the job title to the job duty and connecting it to a value or wage increases. The matrix is categorized by Orientation, Task, Skill, Knowledge, and Management. It can be used for personal career growth by an individual, or for a company to use to develop its people and personnel. A matrix shown to me on a YouTube video that night (Crazy/Hot Matrix) fit what I was thinking and the rest is history. Currently it’s in draft stage and is being honed and perfected.

Why an LMS? Apprenticeship development within a working company is tough to implement, and there are several obstacles to overcome if you plan to execute this within your organization. Welch Tile & Marble started a Department of Labor-approved program in 2005 with the help of DMI from Birmingham, Ala., and updated the program in 2008. The first class to go through the program was eager to learn and to improve their earning potential, but the energy it took to set up a class at night and come up with the lessons and hands-on training was exhausting. These are some obstacles to a traditional apprenticeship program:

  • Time out of busy schedule
  • Canceled class time
  • Lesson-plan development
  • Employee engagement
  • Absent employees
  • Out-of-town workers
  • Make-up class
  • Outdated materials
  • Multiple classes needed Apprentice 1, 1a, 2, 2a, 3, 3a training at the same time
  • Cost
  • Employee financial reward upon completion
  • Economy

The LMS is a must-have for two reasons. First, Welch Tile & Marble has 10 years of experience proving that implementing an apprenticeship program isn’t easy. Secondly, the new generation uses the internet for everything and grew up with instant information access. The vision and mission of the Tile Contractors Apprenticeship and Career Development Program is as follows:

  • Vision: A dedicated investment in developing tomorrow’s leaders .
  • Mission: Communicate, educate, evaluate, compensate, and cultivate the future generations of tile professionals through safety, productivity, passion and critical thinking.

Course Description

The Tile Contractors Apprenticeship and Career Development Program is an organized process designed to:

  • Communicate position descriptions, requirements, duties and responsibilities, measures of performance, and expectations.
  • Establish wage and benefit expectations nationwide.
  • Define career paths for all areas of the tile trade.
  • Develop tasks, skills, knowledge, and management modules to install tile successfully.
  • Provide educational tools, limit risk, and maximize productivity through technology and a positive environment.
  • Evaluate using training modules and certifications.
  • Cultivate passion and culture.

Pay for performance

Pay for performance has always been our belief: provide a good day’s work for a good day’s pay. So how do we provide this pay and who is going to identify what is good? Each market segment, region, work category, and job classification offers a different set of guidelines for what the market will bear and what each company’s core project business operations can offer. This draft is just that, a draft of what an average could be with a market that is diversified. For a company offering a service that is considered a commodity, the cost of doing business is very slim. The workforce is well trained to provide a limited skill with very little flexibility in what they can make available to the end user outside of the core competency. The result is lower pay. For a company offering a service that is considered a specialty, the cost of doing business is larger. The workforce is well trained in multiple areas and has the ability to do projects that are challenging and outside of the norm. The result is higher pay. I hope you are as excited as I am with the Tile Contractors Apprenticeship and Career Development Program and our industry’s attempt to attract new talent, build on their strengths, and move this industry forward. Stay tuned for periodic updates on the progress of the web-based Learning Management System, The Tile Contractors Apprenticeship and Career Development Program, and the refinement of the accompanying Career Development Matrix.

Ask the Experts – June 2015


I am a contractor from Northern California and have been setting tile for 23 years. I did a job where two shower walls cracked. The ceramic tile with a high gloss finish, bought from a local distributor, cracked from the inside. No one is sure why these tiles cracked in many directions. The grout lines did not crack, just the tiles, looking like a crackle or crazing under the surface.

The contractor board and its expert came in. He said I used the wrong materials and did not let the mortar bed cure long enough. He did not say how long a mortar bed should cure and he did not ask me how long before I started to set the tile.

crazingThe materials I used for my float bed include a moisture vapor retarder and 20-gauge stucco netting, stapled into the wall. All these products were bought from my local distributor, and are the same materials sold at all the tile stores in my area.

The inspector said I used the wrong materials. I have used these same materials for 28 years. I was in the tile union when I started and papered and wired apartments in the Bay Area. These are the only products I know, so I was very surprised when I was told I am using the wrong materials. If so, why are the tile stores all selling the wrong materials?

I have spoken with the Northern California Tile Institute and was told that in northern California 20-gauge, one-inch galvanized stucco netting stapled to substrate is acceptable in residential applications not to exceed nine feet in height. This is the application I use as well as most of the guys around here.

I am confused. I do not believe that is the reason the tiles cracked. If you could help me in any way, I would greatly appreciate it. I could give more information if you need it.


You are correct that the method you describe using stucco netting (chicken wire) is considered an “Allowed Local Practice” in your area and is allowed when a local building inspector comes to check your rough-in. A few Northern California counties and cities are pretty much the only places in the USA that do allow this method.

This practice was developed in Northern California by large union shops for tiling tub splashes at a time when tile above a tub extended no higher than 5’0” above the floor height. Also, the tile used with this method was almost exclusively 4-1/4” x 4-1/4” or 6” x 6” white body tile, a very lightweight material. At this point in time, almost all of the companies that developed this method have abandoned its use due to the high failure rate.

There is a faction of Northern California Tile Contractors and Inspectors that are pushing to exclude the use of this method altogether, due to the high risk of failure that affects everyone involved in the project: specifier, general contractor, tile contractor, tile distributor and property owner.

Unfortunately for you, when you use the “Allowed as Local Practice” defense, if you ever do experience a failure, all the risk is yours.  The tile industry standards (TCNA Handbook for Ceramic, Glass and Stone Tile Installation, and ANSI A108/118) make no mention of stucco netting as an approved material. In fact, minimum 2.5 lb. per square yard galvanized wire lathe is the specified reinforcement material. Also, as a California C-54 Licensed Contractor, you are obligated to follow the TCNA and ANSI A108/118 standards, since they are the basis of all regulations regarding tile installation in California.

The cracking of your tile could have been caused by several problems, or a combination of problems such as mortar mixed too rich in portland cement, with an excess of lime, too fine sand, too wet- all could be contributing factors. Also cure time could be a culprit, as you mentioned. ANSI A108 specifies that a minimum of 20 hours at 70 degrees F should be sufficient, but cure times of up to 10 days are desirable. This pre-curing before installation allows the mortar bed to shrink and move prior to covering with tile. Many times stress cracking in tile does appear if the mortar bed is not allowed to pre-cure properly.

I am sorry you are having a failure, but this should sway you that following the TCNA and ANSI standards can truly be in your interest.

Michael Whistler, NTCA presenter and trainer