Stone Floor Care and Maintenance
"I think that one of the most important things in maintaining any type of hard surface is knowing what the flooring is that you're cleaning," said Robert DeCoster, director of operations for HydroTechnologies Inc.
According to DeCoster, mistakes are made when facility managers or building maintenance professionals treat hard floor surfaces as "just another hard floor," whether the floor is composed of granite, marble or slate.
Basic Stone Floor Maintenance
Generally, depending on the surface and traffic, semi-monthly cleaning is recommended. An office or lobby on the 28th floor may need only monthly preventative maintenance and cleaning. An entranceway may require weekly resealing and re-polishing.
"One of the things that can help considerably in maintaining a stone floor is to look at the manufacturer specifications, and not just the materials guidelines," Claudia Ramirez, StoneTech Professional's director of corporate relations, said.
Traffic will dictate much of what a program will entail. A Las Vegas casino might schedule cleaning for the stone floors in bathroom on a two-week schedule and open-area floors weekly, using a cleaner-and-machine combination. Between cleanings, maintenance teams will wet-mop the floors.
"Allow for the proper dwell time," DeCoster said. "When you're cleaning a hard surface, the most important thing is the reaction of the chemical on the surface."
Maintenance begins with proper sweeping and mopping, again taking into account stone type and use. Andrew Levine, president and CEO of Stone Care International, suggests the following basic care steps:
Dust Mopping - Dust/dry mopping removes grit, sediment and loose debris from a floor surface without liquid chemicals. Quick removal prevents scratching and deterioration of the stone surface. While friction from footwear can abrade and dull the crystals in stone, a piece of sediment that is stepped on drastically increases deterioration rates.
Wet Mopping - Wet mopping emulsifies surface soils and prevents residue buildup with the application of a balanced stone cleaner.
Once the parameters of the stone floor are known, the next step is to identify the soil. "You have to know what it is you're trying to remove," DeCoster said. "Once you know, then you need to select a chemical that is going to adequately cleaning that surface."
When a floor needs to be stripped, the chemicals will contact the surface and the pad will scrape it. "When dealing with natural stone, you need a cleaner designed specifically for natural stone," Levine said. "A lot of people like to clean stone with neutral cleaners, but they only clean soft, nonporous surfaces."
This leaves the inside untouched because dirt penetrates the floor via fissures and pores in the stone, making it difficult to remove, Levine said. Most surfactants have an additive designed for a particular natural stone surface to lift the dirt out.
Know Your Cleaner
There are different varieties of formulated cleaners, and not all are appropriate for stone. For instance, an alkaline cleaner can break down the sealer. Many cleaning agents are designed to address hard-water concerns, which creates other decisions for the facility manager to make.
"Chelating agents are designed to grab the minerals out of water so that when you're cleaning in a hard water situation, surfactants can attack the soil like they're supposed to," Ramirez said. "But what are stones made out of? Minerals.
So even if it's not an acid product, you can etch stone with a cleaning agent when it hasn't been specifically designed for your floor type."
When cleaning a stone floor, it is important that the chemical being used is designed for the machine applying it. According to Chase Van Dyne of Viper Industrial Products, different floor finishes respond in different ways to high-speed machines and pads. When a facility manager purchases a new high-speed floor machine, it should first be tested using a variety of different pads to learn which combination reacts best with the floor finish being used.
"Each high-speed floor machine on the market today has variances which make it different from the other units out there," Van Dyne said. "It may have a little higher rpm or a little more pad pressure than the machine the end-user is familiar with." So, he said, each incremental variance in a cleaning situation can have a profound impact when cleaning a stone floor.
"All machines are created differently," Van Dyne said. "The end-user should work with their sales representative to get the right combination of chemicals and equipment to achieve the end result they desire."
It is important that facility managers know the type of stone floor being cleaned and its level of use. How abrasion-resistant is the natural stone? What is its level of absorption, a rough indicator of how likely a material is to absorb water and oil-based stains?
"Knowing those two things, and how (the floor) needs to be sealed and maintained, can guide your maintenance program," Ramirez said. "If it's highly abrasion resistant, it's good as an entranceway because it can take a lot of use. If I want a certain look and use a different stone, it may take more effort. It all needs to be understood on the front end so it fits into the overall maintenance plan. Any care or preventative management is, in the long run, more cost-efficient than restorative care."