Floor coverings: Much more challenging than you might think, says NFCA CEO

flooring
The consequences when the underlying concrete isn't dry before floor coverings are laid

If you thought floor coverings are one of the simplest and easiest aspects of the overall construction process, your perceptions would undoubtedly change after listening to Chris Maskell, chief executive officer of the National Floor Covering Association (NFCA).

Maskell, speaking to a meeting of Ottawa’s Construction Specifications Canada (CSC) chapter in March, outlined the challenges and consequences of failed floor covering installations – and explained how to prevent costly mistakes.

“A $1 billion floor covering manufacturer may put aside two per cent of its revenue for claims,” Maskell said. “That’s $20 million a year – and that’s just for one manufacturer.”

“The two quickest ways to affect margin (bottom line) in business, you can put up your prices, or reduce your costs – our organization (NFCA) is all about supporting industry with the latter,” he said.

There are several problems that add to difficulties in the floor covering sector, which includes various carpet, vinyl, rubber, hardwood, laminate and bamboo floor coverings. Terrazzo, ceramic tile and stone floor installers are covered by a separate set of standards and have their own association.

Issues include a diminishing labour pool, a lack of education and training, and changing products. Regulations restricting the use of Volatile Organic Compounds (VOC) in manufacturing mean that some of the traditional flooring adhesives cannot be used any more – and their water-based replacements are much more sensitive to adverse site conditions.

Other issues include the fact that the floor covering contractors are among the last trades to work on the site, while there is often a rush to meet substantial completion deadlines and a fight to control the budget – and complexities when other finishing trades want to work on the site at the same time as the flooring installers. As well, contractors and owners often run into problems with “boiler plate specifications” that don’t clearly outline requirements and responsibility for items such as proper concrete slab moisture testing and who will flatten the parent concrete before the floor covering contractor arrives on site to start work. Accurate specifications can fix these two issues that so often affect warranties and cause construction delays.

“Floor covering is a skill and science,” Maskell said. Issues to consider include: relative humidity, temperatures, moisture, alkalinity levels, chemical and mechanical adhesion, and surface porosity.

“Flooring is the ‘perfect storm’ for the general contractor,” he said. “How difficult it is to fit flooring into the schedule is underestimated. Complications include (besides budget issues): the fact that the parent concrete slab needs to be dry and warm, installation space must be at ‘service’ conditions, moisture barriers and floor levelling work is expensive, and missing deadlines often results in penalty clauses.”

Concrete moisture often creates havoc for flooring quality, resulting in “wrinkles, bubbles, split seams, dirt traps and even mould” and these aspects can be affected by a variety of factors, including the jobsite’s temperature.

He said there is often confusion between whether concrete is cured, or dry. The curing process typically takes seven to 28 days, which means the concrete has the strength to carry its load, but upwards of 180 days or even longer for it to be ‘thoroughly dry’ for most floor covering and/or related products. Dry times will depend on a variety of things including project location, concrete mix, slab thickness weather and temperature.

Maskell said the only way to be sure the concrete is dry enough is to test it. There are two standard tests available, requiring either probes to be installed in drilled holes (ASTM F2170), or with the calcium chloride test (ASTM F-1869). Guidelines call for three tests for the first 1,000 square feet of flooring, and one additional test for each additional 1,000 sq. ft. Each test point costs about $150 to $200, so for example, the testing for an 80,000 sq. ft. hospital could require a budget of about $15,000, he said. Canada needs more testing agencies that offer this service.

A second issue is flatness. The specifications for the concrete trade (Division 3), and floor coverings (Division 9) are very different. Concrete that is poured in January and meets the required flatness tolerance will not necessarily meet that same tolerance when the floor covering contractor is ready to start, months later. Concrete shrinks, sags (deflects) and curls as it dries. With the deadline looming and the slab now rejected by the flooring contractor, the stage for conflict is set.

“Flatness” has different meanings in Div. 3 and Div. 9 — and misunderstandings can lead to challenging problems.

Specifications drive pricing, scope of work, schedule and contracts, all critical for planning to navigate the challenges of getting flooring installed on time, on budget and with warranty intact.

Finally, there is a need for suitable porosity, or water absorbency in the concrete surface. Without it, an adhesive or self-levelling product may not bond to the concrete surface. ASTM 3191 explains how to take this simple, no cost, 60 second test.

Often there is a need for a “bond test”, where a sample piece of flooring is affixed to the concrete, given time to set, and then tested to see how easy it is to lift up.

Maskell says the NFCA has published an online specifications manual (www.floorcoveringreferencemanual.com) which should help both specification writers, owners and contractors navigate their floor installation issues.

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