Within the floor coating industry, so called “breathable” epoxy is being touted as a new fix for concrete moisture issues. With so much conversation on this topic, it pays to take a closer look. These “breathable” epoxy coatings are permeable, meaning they offer the advantage of allowing moisture to pass through them. While these types of coatings may indeed be appropriate for some facilities, they are not well-suited for all.

Permeable coatings were developed with moisture in mind, to help avoid the risk of surface blistering or other damage due to moisture in the concrete slab or subsurface. However, with such a wide variety of liquid-applied floor coating options—each with their own set of unique advantages or properties—understanding your choices is crucial to ensuring the coating can withstand the demands of its environment. In addition, when selecting a floor coating system, it is important that you understand the difference between hype and reality when it comes to the concept of “breathable” coatings.

Understanding ‘Breathability’

There are two ways a coating can handle concrete slab moisture vapor: Let it through or hold it back. Floor coatings are designed to maximize either one or the other of these capabilities. However, in order to attain true breathability, the coating system as a whole—that is, all the layers—must be fully permeable. Sadly, misinformation can steer facilities in the wrong direction and all too often, a fully permeable flooring system is not attained.

This is especially prevalent in instances where impermeable topcoats are used in concrete coating systems to provide high-performance properties and wear-ability. In such instances, if you apply an impermeable topcoat over a “breathable” epoxy floor coating, you’ll have defeated the purpose in your choice of basecoat—your floor will no longer have the capacity to release moisture and moisture vapor from the slab. Consequently, moisture can become trapped underneath, causing moisture bubbles and other damage to the flooring system.

Performance and Environmental Concerns

Unfortunately, the hype of “breathable” coatings may have also led to a false impression about the types of industries or applications that may benefit from the installation of this type of floor coating. “Breathable” coatings can be useful, but are advantageous strictly in the right environment.

While “breathable” coatings serve to provide some protection to the concrete substrate, permeability works both ways: In and out. Unfortunately, with current technology, “breathable” coatings are just not capable of being both permeable and high-performance.

Industries that use hazardous chemicals or other toxic substances that must be managed in accordance with EPA standards and other governmental regulations are generally not appropriate facility candidates for “breathable” epoxy coatings. Operations utilizing hazardous chemicals, regardless of the care employees take and the protocols they follow, will end up experiencing a splash and spill event at some point. Spilled chemicals can, over time, seep through a permeable floor coating, then through the innately porous concrete slab to penetrate groundwater and soil. It behooves every business to avoid such undesirable incidents for myriad reasons, not least of which are to maintain the satisfaction of corporate stakeholders, positive brand reputation and good corporate citizenship. Lack of proper concrete flooring and secondary containment can lead to the loss of these assets and also include expensive environmental clean-ups, lengthy and costly remediation, as well as compensation payments to members of the surrounding community, based on the potential dangers to which they were exposed.

When Is ‘Breathable’ Epoxy Flooring the Right Choice?

Water-based, “breathable” epoxy coatings have their place, but typically do not hold up in high-traffic areas, where they will be exposed to continuous wear and abrasion. Therefore, permeable coatings are generally more appropriate for light traffic areas, where only low concentration chemicals and moderate pH substances could come in contact with the floor. The presence of any corrosive chemicals in a given facility typically rules out the usefulness of “breathable” epoxy flooring installation.

New Coating Options for Slab Moisture Vapor Mitigation

 Moisture Vapor Transmission (MVT), that is, the phenomenon of under-slab moisture vapor traveling upward through the slab to damage the floor covering above, continues to be researched by industry scientists. As a result, quality manufacturers have developed ways to measure MVT, as well as prevent its effects on flooring, based on test results. The newest moisture vapor control coatings are ideal for addressing MVT challenges in all types of facilities. They can be very effective in holding back the effects of MVT, enabling the installation of impermeable, high-performance and heavy-duty decorative toppings where needed or desired.

These fluid-applied epoxy products can also be helpful with today’s accelerated construction schedules, as they can often be applied within several days of new concrete slabs being poured. The types of products and additives now available for liquid-applied flooring provide options to suit virtually every need and every industry, including:

  • MVT Mitigation 
  • Slip Resistance
  • Impact Resistance
  • Extreme Chemical Resistance
  • Quick Cure Times
  • Thermal Shock Resistance
  • Static Control
  • New Decorative Options (such as colorful solids, quartz, flake and metallic blends)
  • Low Odor
  • Low to Zero VOC Content
  • Sustainability and LEED Green Building Credits

When selecting the most effective, durable, and safe floor coating system, all of these critical factors must be evaluated to ensure the flooring system meets the full scope of facility use. If you have concerns about moisture, a damaged slab or other site conditions, you would be well-served to get accurate information about ‘breathable’ epoxy coatings and whether these products meet the needs of your facility. Get the facts from a flooring specialist who can advise you on a system that will perform for the long term.

Floor System Evaluation Checklist

Selecting the most effective, durable flooring system for your facility can take some careful thought. Factors that should be fully evaluated include:

  • A full inspection of the current condition of the concrete.
  • Moisture testing to determine the relative humidity within the slab, as well as the rate of moisture vapor transmission through the slab.
  • The type of concrete preparation such as shot blasting, scarification or other method that will be required prior to floor installation.
  • The extent to which surface defects such as pit holes, spalls and cracks, may need repair.
  • The specific chemicals, oils, foods, bacteria or other substances that may come into contact with the floor, to help determine chemical and slip resistance needs.
  • Demarcation of areas that will be subjected to heavy equipment traffic, storage, foot traffic, etc.
  • Special requirements, such as electrostatic dissipative (static control) features, support for sanitation or facility hygiene protocols, the ability to withstand the compression of heavy equipment, excessive impact resistance and slip resistance needs, and other design mandates.
  • Cleaning and maintenance practices.
  • Timeline to determine needs such as fast-curing coating options.
  • Budgetary considerations.
  • Décor flexibility, which can include safety markings, embedded logo graphics, as well as customized colors and decorative resinous flooring options.

‘Breathable’ epoxy coatings, when appropriately installed, can be an option for some lighter use applications, but generally will not deliver the level of strength, longevity, ease of maintenance and excellent resistance features (impact, chemical, and slip) provided by impermeable, high performance, fluid-applied floor coatings. Be sure to consult with a local contractor or coatings sales specialist to better understand both permeable and impermeable coating options before making a final decision.