Laying the foundation for good design.
FINISHES AND FLOOR COVERINGS
A thorough review of floor covering and finish choices is important for all areas of new or renovated buildings. In fact, there is a vast array of choices available to commercial stakeholders. But first, Building Teams should briefly survey key trends and recommendations affecting the flooring choice, as well as important information on interaction of coverings with accessories, adhesives, and adjacent building systems.
Wood flooring. A trade survey last year of hardwood flooring retailers and installers indicated that competitive pricing presents the greatest barrier to specification of wood flooring for all project types. Yet many commercial clients prefer the wood aesthetic, forcing design teams to ponder how to deliver a cost-effective, low-maintenance wood floor.
Prefinished and pre-engineered wood products offer potential solutions to this dilemma. Prefinished systems, with ultraviolet- or UV-cured urethane sealants, often contain added aluminum oxide or ceramics to increase durability. “The pre-finishes are even outperforming many site finishes,” says the NWFA’s Kroupa. For those who prefer to finish on site, technology is now available to UV-cure a finish once it has been put down. As for engineered products, which generally offer better stability than natural woods—especially with regard to expansion and contraction—the commercial flooring sector is seeing increased specification rates. Kroupa indicates that more than 50% of the market for wood flooring is for over-concrete applications; engineered wood flooring is specifically designed for installation over concrete.
But even as the technology improves, traditional floor finishes are still popular. “We’re seeing a lot of wax-oil hybrid finishes” in addition to oil and wax alone, says Kroupa, For example, at the Cracker Barrel restaurant chain, all front-of-house floors are finished with hardened oil. Easily maintained by staff with a renovator oil, the steady flow of heavy foot traffic actually rubs the oil into the wood, creating a hard patina and actually increasing durability with usage. “Natural oils and wax are a great option—retro and green at the same time,” says WXY’s Pew.
Resilient flooring. The choice of resilient alternative often depends upon client preference and the usage of the space. Linoleum is a popular choice because of its easy maintenance and green attributes. The composition is largely renewable materials: Lotz calls it “100% green,” and Baisch says it’s “the gold standard.” Both linoleum and rubber flooring offer durability, stain resistance, and acoustic dampening.
Rubber is specified frequently for institutional applications like schools and college facilities, and can be especially beneficial in healthcare settings. According to Hansen, “Rubber can provide foot comfort and back comfort, which is particularly advantageous where occupants are on their feet at length, like in an operating room.” She cautions, however, that rubber-flooring composition can vary. For a good selection, it must not contain recycled tires if it to be used indoors, since tires contain toxic chemicals and were not developed for use in building interiors. Recycled rubber flooring products now usually meet California 1350, “the most stringent IAQ test available,” notes Hansen. “But there are still issues with chemicals used in tire production, which could be released into the air and into occupants’ bodies as the flooring system degrades.”
Linoleum meets a number of initial sustainability considerations, although porcelain tile, ceramic tile, carpet tile, thin-set terrazzo, and cork (including rubber-cork blends) are all viewed as green alternatives by Building Teams. Materials that are typically described as cost-effective options are linoleum, porcelain, ceramic, and some precast terrazzo tiles. “We’re recommending more porcelain tile while the price is coming down due to the Italian market saturating the United States,” says Gensler’s Baisch. Cork, however, faces difficulty in competing on pure cost-effectiveness because it requires careful maintenance.
Many design professionals mention terrazzo tiles and epoxy coverings as excellent options in resilient flooring, although some caution that clients prefer to limit its use due to the upfront cost. “On the other hand, terrazzo will last forever and is easy to maintain,” says Franz, who calls it “the chameleon of floor covering,” in that the material can be precast or cast in place to create a wide array of styles and finishes.
Polished concrete. “Based on sustainability guidelines, I have recommended polished concrete as a low-VOC, low-maintenance option,” says QKA’s Quattrocchi. Polished concrete eliminates the need for an applied surface covering: using specialized polish tools, the concrete floor is beaten, ground, and rubbed until smooth and gleaming. Not every concrete floor is a candidate for polish, but those that are can be transformed into highly durable, low-maintenance surfaces. The sheen can be matte or glossy, and the concrete can be artfully dyed and designed before polishing.
The drawback with polished concrete is the structural concerns: settling and cracking. Though not likely to be a concern for slab-on-grade applications, a polished concrete floor will be unable to conceal any cracking. “We’ve never successfully specified it,” says Hansen. “Even if the client likes the aesthetic, we feel compelled to mention that it could crack,” she adds.
Polyurethane paint can serve as an economical coating for concrete and another alternative to coverings, adds WXY’s Pew.
Infection control. Certain commercial and institutional applications have gravitated toward flooring solutions that control bacteria, fungus, and other sources of infection. This is commonly done with resilient flooring that can be seamed when installed, to be effectively monolithic. Flooring products are often manufactured or installed with an added anti-microbial treatment, but the success and cost-effectiveness of these treatments are not fully verified. “Our extensive research into the topic suggests that by specifying it unnecessarily, we could be doing more harm than good,” says Hansen, with reference to her work in hospitals, labs, and higher education projects.
If there are no seams (or only carefully controlled ones), then a floor likely will not harbor or transfer infectious microbes. For this reason, commercial epoxy, vinyl, rubber, or linoleum are often specified in hospitals, laboratories, kitchens, schools, and daycare facilities. STUDIOS Architecture’s Krochmaluk points to a vinyl floor installed in a back-of-house food preparation area in a corporate project as an example. “We had success with a sheet vinyl product that can be rolled out and right up the wall to create an integral cove base,” he says. The joints can be heat-seamed to create a monolithic, microbe-resistant floor. Best of all, the integral base eliminates a typical area where food particles and dirt might collect, easing O&M needs.
Accessories. Flooring is never truly monolithic across a full building floor. There are joints and seams in places where one flooring type meets another, or where the flow of materials intersects with a dissimilar building system like a partition or door, thus creating potential aesthetic and maintenance difficulties. Ideally, transitions should always be flush and aesthetically seamless. Careful attention to joints also can pay off in enhanced client satisfaction.
“Where a corridor meets a restroom floor, the designer should give careful consideration to making a nice, effective transition,” says Hansen. Sustainable design principles are just as important when it comes to accessory components: metal and wood may be preferred over other materials, depending on their material makeup and maintenance requirements.
Some Building Teams give preference to flooring systems whose manufacturers provide products or guidance on suitable trim and joint detailing. Unfortunately, not all wood flooring manufacturers produce all the necessary trims, saddles, joints, and especially nosings (for stair landings and other drop-off points) to match every species, says Kroupa. These accessories may have to be fabricated in a mill shop, adding expense.
In terms of ADA-friendly and hazard-free interior designs, Building Teams may favor headers and feature strips to T-moldings, because flush joints eliminate tripping potential and may be preferred aesthetically. Another safety consideration: glare. “We try to avoid using thresholds with a high glare factor,” says Quadrangle’s Robbie. “They can be difficult for people with low vision to distinguish.” Building Teams should consult manufacturer literature and technical representatives to select appropriate accessories, joints, and trims, say experts.
OPERATIONS & MAINTENANCE: GROUND-LEVEL STAKEHOLDERS
Floors must be specified to meet the needs and likely habits of those who will clean and maintain them. Wherever possible, the facilities manager and even the operations and maintenance crew should be on the list for project communications, so that the floor can be maintained correctly from occupation through the life of the building.
Every building professional can offer a poignant example of maintenance-related flooring failure. “We specified cork floor, which worked well and looked great,” STUDIOS’ Krochmaluk recalls. “But a cleaning crew went at it with water and a wet mop. In no time at all the cork peeled off.” His recommendation for bigger projects with large facilities crews? “Keep it simple.”
Basic, durable, low-maintenance finishes are going to be preferable in most project types, according to the experts. Lotz suggests it is wise to assume that maintenance budgets are going to be underfunded, so Building Teams should specify with that reality in mind. The experience and attendant knowledge of the maintenance crew should also be assessed and factored into decisions about finishes.
Other operations and maintenance issues should factor in to questions of cost-effectiveness and long-term return on investment (ROI). “Vinyl resilient tile is seen as low-cost compared to rubber tiling,” says Robbie. “But the ongoing waxing and stripping requirements, versus simple damp-mop cleaning for rubber, can mean very high O&M costs.” The wood floors described earlier at Cracker Barrel restaurants offer a similar example: specifying prefinished wood may be less expensive up front, but a wood floor with an added finish that becomes more durable with heavy foot traffic (and simple maintenance) will likely present long-term cost savings.
Most designers agree that manufacturers bear some responsibility for communicating to the design team and to the facilities crew what is required to properly maintain the flooring. Rappoport even feels that the floor finish-material supplier is obliged to train the client’s cleaning staff in order to avoid a situation that could damage the installed finish.
There is also the question of sustainability and green design. Franz advises his clients, wherever possible, to use floor finishes made from natural materials, such as flamed stone, unfinished wood, and the like. These materials offer a beautiful aesthetic with low maintenance requirements, and can become more beautiful with age and wear, he says.
Others, including Hansen, strongly recommend finding out from the manufacturer if they have a green-cleaning protocol in place. “The products we specify have to be maintained for a very long time, even for the life of the building,” she says. “We want the flooring to last as long as possible, and we want the IAQ to be optimal for the building occupants and maintenance staff.” +
FURTHER READING REQUIRED
To complete the reading and take the exam to earn 1.0 AIA/CES learning units, go to www.BDCnetwork.com/CommercialFlooring.