There are several factors that contribute to how long a concrete sealer actually lasts for, but the life of many types of concrete sealers will fall into a very specific time frames.
- Silicate Concrete Sealers: Silicate concrete sealers never break down. They spark a chemical reaction in the concrete in order to form a calcium silicate hydrate structure within the pores. Once that structure is formed, it can only be removed if the concrete itself is removed.
- Silane Siloxane Water Repellent Sealers: Silane-Siloxane water repellent sealers will last anywhere from 6 months to 10 years depending. Low solids solutions with recycled resins will last 6 months to a year, while higher solids solutions with non-recycled resins, like the Armor SX5000 and SX5000 WB will last for up to 7-10 years.
- Siliconate Water Repellent Sealers: Like with Silane-Siloxane water repellent sealers, Siliconate sealers will last anywhere from 6 months to 7 years. Most low solids solutions found in store will last 6 months to a year, while higher solids solutions, like the Armor SC25 will last for up to 5-7 years.
- Acrylic Concrete Sealers: Acrylic sealers last 1-3 years before they need to be re-coated.
- Epoxy Coatings: Epoxy coatings last 5-10 years before they need to be re-coated.
- Urethane Coatings: Urethane coatings last 5-10 years before they need to be re-coated.
There are several factors that contribute to the actual life of a concrete sealer:
- The quality of the product applied. There is a large difference in quality from one product to the next. The percent solids, the source of the raw materials, and the actual formula will have a large impact on how well a product performs and how long it lasts.
- The amount of coats applied. This is actually a very important factor. Unless the sealer specifically requires 1 coat, most sealers should be applied in two coats. The first coat tends to soak up in to the surface of the substrate, leaving minimal surface protection. The second coat will bond to the first coat, allowing for better protection on the surface. Silane-Siloxane sealers, acrylic sealers, epoxy coatings, and urethane coatings should always be applied in two coats to achieve the longest life.
- How the product was applied. Penetrating sealers should be applied with a sprayer, and coatings should be applied with a roller. If you apply a penetrating sealer with a roller you risk applying too much or not enough sealer, and if you apply a coating with a sprayer you run the risk of not applying enough product.
- The current condition of the substrate. If there are issues with the substrate it can shorten the expected life of the sealer. For example, deterioration, old sealer, water or moisture – those can all play into reducing the life of a sealer. Porous substrates require more material and dense requires less. You need to be able to adapt to the substrate in order to provide the appropriate amount of material.
- The environment in which the sealer was applied. This is a key factor, especially when applying sealers to an exterior surface. If you apply a sealer in the morning, dew can be present on the concrete. If you apply a sealer in the middle of the day, the concrete could be hot and cause issues with curing. The best time to apply a concrete sealer outside is in the late afternoon or early evening.
- The suitability for the project. Choosing the right sealer is one of the most important factors in achieving optimal life. If you apply a urethane or epoxy coating to exterior brick, expect that it will fail. If you apply a silicate sealer to stone, expect to get white crystal formation on the surface. Sealers have very specific uses and applying them outside of their suggested uses can result in sealer or coating failure.
- Not properly preparing the surface. The surface of the concrete should be clean, dry, and properly prepared. If a coating requires you to grind the concrete, it should be ground. If you are applying a penetrating sealer, there shouldn’t be a coating down. Surface prep is very important.
There are many factors that contribute to the actual life of the concrete sealer or coating. For best results, follow the manufacturer’s instructions, and if you have any questions, contact a product technician before purchasing. Applying the product to a test area will also help to determine suitability, coverage rate, and performance abilities.