Home Depot stores started the current trend several years ago when they chose plain concrete as a finished floor surface. More recently, some stores included integrally colored feature areas. Grocery stores, in particular, added color in produce areas, later coloring the entire floor when the floor proved to perform well. Today retail construction is installing colored concrete floors, replacing products such as vinyl tile, quarry tile, wood, and carpet.
This trend isn't happening because integral color is the latest new product in the marketplace. Its origins date back to 1915 and was one of the very first products for decorating concrete. Over 93 years there have been many integrally colored floor installations, but not like today. So what makes the difference?
Shifts in owner attitudes
As you might expect, the central concerns of owners of commercial properties are related to cost and maintenance over time. But aesthetics are important as well and there is considerable interest in colored concrete. A number of factors are influencing these decisions.
- After many years of experience with other flooring systems, owners discovered that colored concrete is less costly to maintain.
- Maintaining floors with wax systems can be costly over time. Vinyl tile floors, in particular, require daily cleaning and waxing.
- Some floors on ground have problems with moisture vapor transmission. Impermeable finishes, such as vinyl tile, quarry tile, carpet installed with adhesives, and coatings such as epoxy, intensify the problem and result in expensive repairs. It is better to avoid moisture vapor problems entirely.
- Colored concrete can be sealed with penetrating breathable sealers that look very attractive.
- By increasing the gloss number of a concrete floor, lighting can be reduced to save energy.
- The aesthetics offered by decorative concrete finishes increasingly are popular today.
- Owners like the gentle mottled and variegated color appearances that can be obtained with integral color combined with contractor finishing techniques.
- Owners have become interested in construction that results in LEED certification and concrete wins LEED points.
Trends on the jobsite
The development of liquid dispensed coloring systems makes it easy for ready-mix producers to batch colored concrete. This technology also gives owners of commercial retail stores a number of colors to choose from. Many owners select one color for all their new stores. Color manufacturers then preblend the color and ship it in totes with dispensing equipment to ready-mix producers who don't own the equipment but have the contract to supply the colored concrete. Owners sometimes also specify that only liquid dispensed coloring can be used on their projects.
Just adding color to concrete doesn't provide owners with what they are looking for. All the steps in an installation system become important, starting with durable concrete mix designs having low water-cement ratios which are more impermeable and help to minimize efflorescence problems. To increase color variegation, some specifiers want contractors to do limited hard troweling during the finishing process.
Most retail construction requires wet curing with the use of cover-curing membranes, preventing the use of chemical curing membranes that can't be completely removed afterward. Wet cured floors have increased strength and greatly improved resistance to abrasion. The key is to immediately clean slabs after removing the covers to get rid of all hydration byproducts. Contractors have learned how to do this effectively.
The application of penetrating sealers, such as sodium and lithium silicates and siliconates, is part of the system as well. They add gloss to a floor surface and enrich the appearance of color without interfering with the breathability of a slab. They don't resist stains and acids, however, so owners must commit to spot maintenance when spills occur.
Diamond polishing is a popular way to improve the floor reflectivity and the results provide elegant finishes. More recently, the introduction of strip pads with diamonds embedded in the fibers offer a way to polish hard-troweled floors without cutting appreciably into the finish. Maintenance staff then use the pads on their floor maintenance machines to maintain the gloss as foot traffic wears it away.
The Way It Is
I received a call from a small decorative concrete contractor to tell me about a job problem. He's been a decorative concrete contractor for his entire working life and is known for his craftsmanship and attention to detail. Last fall, he installed a 5000-square-foot floor and this spring he lightly profiled it, applied a water-based stain, and then sealed the work with a water-based acrylic sealer. A week later the owner called him and said the finish was scaling everywhere. The contractor and his crew spent a week scraping off the stain and sealer. He called the manufacturer of the stain and was asked if tiny dimples appeared about ½ inch apart as the material was being applied. He said yes and then was told that the product had frozen somewhere in route from the manufacturer to the supply house where the material was purchased. Because the contractor is located in California (in a nonfreeze area), it was clear that the damage occurred before he took possession of the product. The manufacturer immediately offered to replace the product at no cost but the contractor would have to pay for the labor to remove and replace the finish, a cost close to $15,000—many times more than the cost of the material.
This situation isn't all that unusual because most manufactured material warranties only cover the cost of the product when they are judged to be faulty. Manufacturers feel this is fair because they can't be responsible for how contractors handle their products. But contractors often get stuck holding the lion's share of the liability when things go wrong, even when it's the product that fails, and in the case described here, it's a fair question to ask how much they should be expected to know about the products they use. Should this contractor be expected to know what this product would look like if it had been frozen on route to the supply house? I often say that it's not what you know that gets you in trouble; it's what you don't know. Should this contractor be expected to know what the product looks like after it freezes? Concerning finances, where is the right place for manufacturers and contractors to meet?