FAQ- What is the Major Cause of Premature Coating Failure on Concrete By John Bennett, CEO, Eco Safety Products What is the Major Cause of Premature Coating Failure on Concrete? While there are many application and substrate variables that may lead to premature coating failure, the single most important prevention is proper surface cleaning and preparation to ensure optimum lifespan of your coating project. This process is often viewed as insignificant cleaning and you want to get on with the artistic work. This is by far the least glamorous, and the urge to take shortcuts is tempting. If you are a contractor, time is money and the client has a deadline of yesterday. Or if you are a Do-It-Yourselfer (DIY) and excited to get the project done and you just can’t wait to see the finished product. Trust me, once you invested time, money, and sweat the last thing you want is a “redo” anytime soon. Take extra time now for this process and save time, money, body/headache over the long run. Keep in mind that the overall success and performance of stains, sealers, and other coatings on new or existing concrete substrates are highly dependent on the quality and attention to detail during the surface preparation process. When installing a penetrating decorative concrete stain such as SoyCrete™, you will find that the extra detail will provide you with more decorative and artistic options, not to mention a more beautiful end project. The main objective is to achieve the highest degree of cleaning and surface profiling that will allow the chosen coating material to reach its optimum penetration and/or bonding strength that is equal to or exceeds the tensile strength of the substrate that the material is being applied to. If there are limitations to performing thorough surface preparation, you must be prepared to accept a lower expectation level of the coating lifespan. For instance, if you install a coating over dust and dirt, you are bonding to dust and dirt which has zero bonding strength to the concrete. Likewise, if you install a coating over an existing coating that has a weaker bond than the new coating or one that is already beginning to flake, your new coating will only be as strong as what it is applied to. When that area gets enough abrasion (very little) the coating will come up. If you are applying a penetrating stain which needs to penetrate into the surface for long lasting results without ever peeling but you fail to properly open the pores to allow penetration, it will reside on top with a weak film and will wear prematurely. If you stain or coat over efflorescence, you are simply attaching to loose soluble salts that will easily be removed through abrasion. On the other hand, if you have a thoroughly cleaned surface with optimum porosity, whether you are installing a penetrating stain or a topical floor coating, the material will achieve maximum absorption and will bond more deeply within the substrate providing significantly longer life span than one having a weak grip on a non-porous surface. What to Look For: Thoroughly investigate the surface for contaminants, defects, internal contaminants, bond breakers, and potential moisture vapor transmission problems. Look for signs of dusting, cracking, efflorescence, water, oils, curing compounds, form release agents, and laitance. New concrete is not an excuse to overlook detailed evaluation and preparation. Curing compounds are liquid materials that are commonly applied to newly placed concrete to allow hydration curing by retarding water from evaporation. If it hasn’t dissipated or is not removed, this will be a bond breaker. You may also find form release agents which are applied inside the forms to facilitate the release and removal of the forms. These release agents do not allow the forms to stick, thus will not allow materials to absorb or bond as well. Additionally, the density or porosity level of the concrete will vary by the type of concrete mixture and the finishing method used. Laitance (a thin, weak cement layer of partially hydrated cement paste) also leads to premature failure as these areas have a weak bond.