With so many concrete sealers on the market, it can be hard to figure out which sealer is the best sealer for your concrete application. To help make that decision easier, we wanted to put together a concrete sealer buying guide to help you make the best decision for your concrete project.
Before choosing the best sealer, you need to evaluate what you currently have down. If your concrete is sealed, it may have an impact on what you can reseal your concrete with. Here are some of the most common types of concrete sealers, and what you can use to reseal them with:
- Concrete Densifier: Concrete densifiers work entirely below the surface. They won’t leave a film or coating, and they don’t offer any beading characteristics. For that reason, just about any sealer can be applied to concrete previously sealed with a concrete densifier so long as it has been at least seven days since the densifier was applied. Examples of concrete densifiers are sodium silicate sealers, and lithium silicate sealers like the Armor S2000 and Armor L3000.
- Water Repellent Concrete Sealer: Water repellent sealers work entirely below the surface, but they deposit a material in the pores that reduces the movement of water and moisture through the concrete. For this reason, you have to be careful when it comes to putting another sealer over a water repellent sealer. If it has been a few years, and water no longer beads, you may be ok to reseal with a sealer of your choice, but the concrete technician will likely have you run a few tests on your concrete just to make sure. If it has been less than 3 years, or water still beads, you need to proceed with caution. You can’t reseal with a water based sealer or coating because the water repellent will repel the sealer. You can reseal with most solvent based sealers, but depending on how aggressive the water repellency is, this can be risky. While oil can move through water, the pores are still taken up with a hydrophobic material so the concrete won’t be as porous as unsealed concrete. You could end up with dark spots, or coating failure. If you applied a water repellent sealer in the past and are looking to reseal, it is best to talk to a technician and try a few samples first.
- Acrylic Sealer: A general rule of thumb is if you have a water based acrylic sealer down you want to reseal with a water based acrylic sealer, and if you have a solvent based acrylic sealer down you want to reseal with a solvent based acrylic sealer. If you apply a solvent based acrylic over a water based, or a water based over a solvent based, you will have adhesion issues and coating failure. If you have a water based down and want to switch to a solvent based, or if you have a solvent based down and want to switch to a water based, this can be done but you will first need to completely remove the old coating from the surface and within the pores which typically requires chemical strippers like the Armor CR100 and pressure washing. If you have any questions, it is always a great idea to talk to a technician first so they can guide you through surface preparation and answer any compatibility questions you may have.
- Concrete Coating (Epoxy, Urethane, etc.): If you have a coating down, it is best to talk to a technician. There are many types of decorative coatings on the market, each with their own list of compatible topcoats.
If your concrete is currently unsealed, you are free to use the sealer of your choice. Each type of sealer comes with its own list of benefits and characteristics. When choosing a concrete sealer you want to take into consider 1) what you want your concrete to look like once sealed, and 2) how long you want the concrete sealer to last and what you want it to offer in terms of performance. Below is a list of the most popular types of concrete sealers and what they offer in terms of life and performance.
Type of Sealer | Appearance | Benefits | Life | Products |
Silicate Sealer | No Change | Increases strength and density of concrete. | Lifetime | Armor S2000, Armor L3000 |
Silane-Siloxane Sealer | No Change | Reduces water absorption through concrete pores. | 7-10 Years | Armor SX5000 WB, Armor SX5000 |
Solvent-Based Acrylic Sealer | Wet Look, low to high gloss, clear and color options | Enhances and protects concrete | 1-3 Years | Armor AR350 (low gloss), Armor AR500 (high gloss), Armor WL550 (matte) |
Water-Based Acrylic Sealer | Low to high gloss, clear | Enhances and protects concrete | 1-3 Years | Armor WB25 (high gloss), Armor WB15 (low gloss) |
Concrete Coating | Low to high gloss, clear and color options | Enhances and protects INTERIOR concrete | Varies | Armor Epoxy, Armor UTN60, Armor UTX60 |
With all the concrete sealer options, which sealer is the best for you?
If you are looking to seal your concrete without changing the look or color, water repellent sealers are a great option. They reduce water absorption by up to 95%, therefore reducing damage and deterioration caused by water absorption such as cracking, spalling, and staining. It is a very popular concrete sealer if you are looking for a great, long lasting sealer, that offers your concrete some protection against the damaging effects of water absorption. Now, as you can see above there are two types of sealers that won’t change the look or color. There are water repellent sealers and densifiers. Densifiers are great, but they aren’t always necessary and they don’t offer any benefits when it comes to protection against outdoor elements. Densifiers are great if your concrete is showing signs of damage and deterioration caused by surface abrasion, such as concrete dusting. You can apply a densifier, wait a week or two and then apply a water repellent sealer, but often times this is overkill and not needed. The use of a water repellent sealer alone is pretty powerful. If you have questions about what your concrete needs, you can run your application by a technician and they can guide you toward the best concrete sealer for your application.
If you are looking to seal your concrete, and want a wet look or gloss finish, then an acrylic sealer is a great option. If you want to darken or enhance the color of your concrete, you want a solvent based acrylic sealer. If you don’t want your concrete to have a darker appearance, but you want a low to high gloss finish, then a water based acrylic sealer is a great option. Solvent based acrylic sealers are more popular, simply because they are very easy to apply, fix, maintain, and recoat. If you experience hazing or white spots from curing issues with the coating, solvent based acrylic sealers can easily be repaired with Xylene. Also, when it comes time to recoat, you just apply a fresh coat to a clear and dry surface. With water based acrylic sealers, Xylene won’t work. If the coating hazes or develops white spots, often times you will have to remove the damaged areas. When it comes time to recoat a water based acrylic, you may need to screen scuff the surface first to allow for adhesion. The benefit to water based acrylic sealers is that there is little to no odor, while solvent based acrylic sealers tend to have a strong odor that takes a few days to dissipate. Every sealer is different, and every situation is different. As a third option, you have a sealer like the Armor WL550 which is a combination of a water repellent sealer and an acrylic. While the Armor WL550 will slightly darken the surface, it won’t leave behind a visible surface film. If you have questions about which sealer is best for your concrete, or if you have questions about application and recoats, feel free to talk to a technician and apply a few samples before purchasing.
Epoxies, urethanes, and waxes are great solutions for interior floors. Epoxies are great for residential applications and as bonding primers, urethanes are great for applications where oil, gas, and chemical resistance are required, and waxes are great for maintaining the gloss level on already coated surfaces, and for a quick and easy alternative to changing your floor appearance. If you are considering an interior coating it is best to talk to a Foundation Armor Technician first so they can get a good idea for your application, and guide you through the choosing the best product for your application.