New York—Concrete moisture. It is an issue that has not just affected the entire industry but industries that intertwine with floor covering—from architects and designers to concrete manufacturers and end users. It is even a catalyst behind another rapidly growing problem: mold. The problem is so big, it is estimated that annual moisture-related flooring problems have hit the $1 billion level in the U.S. alone. As a way to help provide some answers to those within the flooring industry as well as architects, designers and anyone else interested in the issue, StarNet recently completed a 12-city national speaker series called, “Mix: The concrete truth about concrete moisture.”

Lori Dowling, president and CEO of the commercial flooring cooperative, said the concrete moisture dilemma is “a very significant issue that affects everyone involved in construction—whether it be residential or commercial.” What makes the problem even more compelling is there are so many factors that can contribute to it than to just blame one party as being responsible is ignorant. Dowling called it “the mother of all technical issues; there are no easy answers.” One of the biggest industry groups to be affected by this issue is the commercial flooring contractor who routinely finds himself caught between the specs of the architect/designer and the conflicting desires of the general contractor/ owner and the floor covering manufacturer.

At its annual educational conference last November in Tucson, Ariz., Star-Net undertook the cause of presenting its mem bers with a detailed half-day course on the various issues surrounding the issue and ways to get it under control so that all parties involved can successfully complete their projects ( FCNews, Dec. 8/15). The seminar was so well received, StarNet decided to package it into Mix, a fast-paced two-and-a-half-hour session, and took it on the road so as to reach as many people as possible. And it worked, as over 900 professionals participated in the program, with some cities drawing well over 100 people. “It was not only well received,” Dowling said, “it was greater than expected. This is certainly a subject that is on top of everyone’s mind; the timing was perfect.

“This was really a double whammy,” she added, “because StarNet members brought some of their own people who were not at the Tucson event but felt needed to see the information being presented. Plus each meeting we saw a bunch of people from the A&D community, as well as facility managers, construction people—basically anyone writing specs and involved in the construction process.” Sponsored by Mohawk Industries, Armstrong World Industries, Nora Rubber Flooring and Ardex, each session featured two of the most respected leaders in this particular field—Peter Craig, an independent concrete floor consultant with the firm Concrete Constructives, and Scott Tarr, a senior evaluation engineer with Construction Technology Laboratories.

Beyond just gaining the most up-to-date information on the subject of concrete moisture, Mix qualifies as a continuing education (CEU) credit through the American Society of Interior Designers (ASID), International Interior Design Institute (IIDA), and American Institute of Architects (AIA). Dowling noted, one of the most important things Mix brought out is, “There are no easy answers, and this was certainly not the final sayso. There are many different and diverse opinions on the subject, from who is responsible for testing to who is responsible if there is a product failure due to moisture.” While opinions and feelings on the subject vary depending on the person’s role in the chain, she said the issue itself is universal. Even though sessions were held in major markets in every part of the country, the questions, testimonials and feedback were virtually the same.

“Even in places where you would not normally associate with moisture, such as in Phoenix,” she said, “the problems were similar to those in Seattle. Everyone who attended had either experienced a concrete moisture problem first-hand, had their companies involved at some time or know someone who has had to deal with it. So, not only was the timing appropriate, so was the content because attendees really soaked up the information and were consistent with their comments.” Both Craig and Tarr stressed that one of the reasons for this issue becoming the problem it has is due to a lack of communication by all parties involved. “We’ve been in a reactive mode,” Craig said, “whereas we need to be proactive.”

He pointed to at least a half-dozen factors that can and have played a role in concrete moisture besides the concrete: irrigation around the structure, broken pipes in and around the structure, condensation, humidity, adhesives and maintenance. In fact, “sometimes moisture has nothing to do with a product, the concrete or the environment, but rather the owner of the structure.” It is for this reason that all parties need to stay in constant communication with one another. As both presenters noted, Does a designer know there is a moisture issue when the concrete spec is developed? Engineers and architects must shake hands and work together. In fact, everyone has to work together because all parties are starting to be sued. Plus, it saves time and money by doing this because it allows changes to be made prior to the project starting as opposed to when it is supposed to be nearing completion.

[Editors note: in part two we will look at some of the discussions which took place at the seminars.] “The chain of responsibility falls on everyone,” said Tarr. “All parties are connected to each other and no one wants to be the weakest link. One of the big things that needs to be thought out from the start is the future of a facility’s floor. Will it always be a warehouse or can it eventually become a store or a place where people live? Each has its own unique design elements and their affects on the concrete need to be taken into consideration.” Though many things can contribute to a moisture-related problem, the concrete itself is still, by far, the biggest factor. Much of this due to today’s fast-tract construction mentality which does not take into consideration the proper amount of time needed for a concrete slab to be sufficiently dry enough to successfully lay a floor covering over it.

Craig said a quick look at how a typical slab not only illustrates this point but shows why this such a difficult process. On average, it takes 275 pounds of water per cubic yard to bring cement to a workable solution, known as slump. That means, to make a typical 1000-sq.-ft., 4-in. thick concrete slab, 1,697 pounds of free water is added. “That’s a lot of water, and it doesn’t take into account any moisture below the slab.” This is for what would be called traditional concrete. Nowadays, many general contractors are using newer, lightweight cement, which has created further problems because as Tarr noted, “it is pourous and takes a much longer time to dry, sometimes as much as three times the length—and that is only at mid-depth.” It is for this reason Craig stressed, “You have got to take the ground out of play. And there are methods now that are cheaper than ever.”

Craig then went on to describe the numerous ways this can be done, including the pros and cons of the different types of vapor barriers, blockers and other products on the market today. He noted many of the products out there offer vast improvements over those from as little as five years ago, especially in the area of vapor barriers. “There is a new generation of plastics that are overcoming many of the old issues. And, the cost of these are very reasonable and no longer an issue within the budget.” Tarr used his segment to talk about the various moisture testing methods, including how they work and what their results mean in relation to the overall project. “There’s qualitative and quantitative tests,” he explained. “The first is more of an idea and gauge while the other is definitive. The problem is that methods test for moisture being emitted from the concrete but temperature and relative humidity are two major factors in influencing a test. In fact, there is more moisture absorbed from the air than from a concrete slab over water.”

Tarr said both tests “bring something to the table” in helping get a better picture of what is taking place. The main thing is that you need to get as much information as possible—about the concrete, construction site history and moisture measurements. You need to employ a scientific approach. It’s not rocket science, but you still need to beware of limitations from the tests and use the results with other information.” Beyond all this, Craig and Tarr said another major consideration is how the floor covering itself plays a part in the process. Not all adhesives are the same, nor are carpet and resilient backings and, for that matter, each type of floor covering requires a different set of parameters. “The most reliable approach to mitigate water on new concrete is to do it right from the start,” Craig offered, including: take the ground out of play; use a practical water-to-cement ratio; cover the slab while curing; allow for ample drying time and climateization; get designers to understand the slab must be dry if they want to use floor coverings, and, then, have an independent test done. That’s the perfect world, in reality most projects will require some of water mitigation.

“Can we avoid water related problems?” he concluded. “Yes, but first everyone involved in the construction process must communicate with each other so that issues can be taken care of before it’s too late.” With the Mix series being so well received, Dowling said StarNet is discussing bringing to other markets in 2005 as well as the possibility of creating different programs and revisit the the cities from the this round. “There are a number of other industry topics that have broad affects and if we can take the lead in educating those involved, it doesn’t just benefit our members but the entire industry because it can help reduce costly claims.”