What is the difference between a concrete sealer and a concrete coating? Generally speaking a concrete sealer is a penetrating formulation or a lighter topical solution that either seeps into the concrete or is suspended on the surface. Concrete sealers are usually classified as acrylic sealers, silicate sealers and silane/siloxane formulations. A concrete coating on the other hand sits on the surface of the concrete and builds up and protects through the layers of coatings. Concrete coatings are usually classified as epoxies, urethanes and polyaspartics.
Concrete Sealers:
- Silicates: penetrating sealers in either a sodium, lithium or potassium carrier that seep into the concrete, chemically react to form calcium silicate hydrate and thus densifying.
- Silane/Siloxanes: water repellents that form a hydrophobic barrier to seals out moisture while chemically bonding with the substrate.
- Acrylics: water based or solvent based decorative sealers that enhance the surface and repels water.
Concrete Coatings:
- Epoxies: coating used to prime or coat concrete to stop dusting, add chemical resistance and abrasion resistance properties.
- Urethanes: coating usually applied on top of an epoxy to add additional protection from chemicals, wear and UV rays.
- Polyaspartics: fast drying urethanes applied on top of an epoxy with a faster tack free dry time
Concrete sealer and concrete coatings manufacturers: Kretetek, Eagle Sealer, H&C, LMCC, Moxie, New Look, Okon, Prosoco, Scofield
When it comes to garages and warehouses they require a tougher, durable, chemically resistant coating. Urethanes, especially aliphatic urethanes, are stronger, more chemically resistant, UV resistant and have a higher abrasion resistance. If you have an industrial warehouse and you decide that you need to seal it you have two options: a concrete densifier or a urethane coating. Concrete densifiers are excellent choices if you need to harden, dust-proof and increase the abrasion resistance of a warehouse. However if you need extra chemical resistance you need an aliphatic urethane coating.
Urethanes are easy to apply and can last up to ten years if you follow all of the proper precautions and instructions. The first step you need to take when applying an aliphatic urethane is to grind the existing concrete surface. By grinding the concrete you are creating a tougher surface for the products to adhere to so it will not scratch or peel after application. After grinding the concrete you need to mix Part A components to Part B components and apply using a squeegee. By using the squeegee you can elongate the coverage and it allows for the proper mil coverage. After squeegeeing you need to back roll the surface and then let the Urethane dry for 3-5 days to completely set.
Our Take: Urethane coatings that have held up the best for the longest time period are Urethane 645, Superior Industries Aliphatic Urethane , and APF’s Polyurethane 250 High Performance Concrete Sealer.
Concrete, by nature, is extremely porous filled with endless pores and capillary voids. Think of a sponge, when dry it is hard and dense but when it comes into contact with water it fills up and becomes weak and wet. In order to prevent concrete from seeping up endless amounts of water a waterproofing concrete sealer should always be applied. Concrete basements, concrete driveways and concrete foundations should always be treated with a waterproofing sealers since they are most susceptible to damage.
If a basement is composed of concrete blocks or concrete cinderblocks it is best to use a Silane/Siloxane based sealer. The mixture of the two types of sealers and the larger size molecule will provide excellent water repellency to the overly porous blocks. Concrete blocks are the most porous concrete structures since the pores and voids are large and the thickness of the concrete is not extremely deep. It is essential that a concrete block basement is sealed as soon as possible to prevent water damage from the close proximity of the water table.
If it is a poured concrete foundation or a concrete driveway it is best to use a penetrating densifier and waterproofing blended sealer. The combination of the smaller molecule with its densification properties and the larger molecule with its waterproofing properties is the ultimate solution for preventing the penetration of water.
Our Take: Excellent silane/siloxane concrete blocks and cinderblock sealers include Okon S-40 and Siloxa-Tek 8500 and penetrating densifiers and waterproofers include Lithi-Tek 9500 and Euclid’s Diamond Hard
What makes a decorative concrete sealer standout amongst a crowded industry and multitude of products? Decorative concrete sealers for the sake of this article are acrylic top coats that will protect, enhance and beautify concrete. Acrylic concrete sealers have been the decorative choice for many years and can leave anywhere from a glossy finish to a satin shine finish. They come in solvent based varieties that are applied by nap roller or they come in water based versions that are applied by sprayer.
Decorative concrete sealers are ideal for patio pavers, pool decks, stamped concrete and driveways. Solvent based varieties usually leave a glossy finish which can cause concrete to become slippery when wet. Certain brands sell a non-slip additive that can be added to their sealers if a high gloss finish is desired with less risk of slippage. One of the most popular decorative sealers is a water based acrylic. They comply with VOC regulations so they can be used in all 50 states. They do not leave a slippery finish, they enhance the concrete while repelling water and they protect from the suns harmful UV rays.
Our Take: Choose a water based acrylic over a solvent based acrylic. Reputable acrylics we have found are Everclear VOX, Cryli-Tek 5500 and SC-42 WB
Concrete is extremely porous by nature filled with small capillary pores and voids that are extremely susceptible to damage from cracking, spalling, water, moisture, mold, efflorescence, and hydrostatic pressure to name a few. In order to prevent all of these disastrous situations there are a few methods of prevention. A concrete densifier is the most effective solution to help prevent concrete from degradation and deterioration. A densifier is usually silicate based in either a sodium, potassium or lithium carrier. Out of the three, the lithium seems to be the most effective since it is a newer technology with less risk of concrete whiting and hazing.
Concrete densifiers are penetrating formulas that seep into the concrete, reacting chemically to form additional calcium silicate hydrate thus strengthening and hardening a concrete slab. The slab is then protected from cracking and spalling. Some densifiers claim to waterproof but these are false claims unless the silicate densifier is combined with a waterproofing siliconate molecule. They are known as silicate siliconate blends that are excellent densifiers and waterproofers. Densifiers are also ideal for polishing, grinding and burnishing concrete. They are usually applied before and after polishing concrete adding extra protection and strength.
Our Take: State of the art densifiers are LiON Hard, Lithi-Tek 4500, and Liqui-Hard
Basements are known for water, moisture, mold and mildew problems. Since basement foundations are underground they are usually in close proximity to the water table. This creates a problem since water tends to mitigate towards the walls of the basement; especially during rainy seasons and during springs inevitable snow melting. There are many companies out there that offer basement waterproofing solutions but only a handful that truly live up to their claims. Over the years we have found the best way to prevent basement moisture and water damage is early prevention. By sealing a homes foundation when it is first poured is the best kept secrete when it comes to basement waterproofing.
When looking for a sealer look for a penetrating, waterproofing sealer. Acrylics, epoxies and urethanes will all peel up and will not adhere at the first sign of water. Silicates alone are marketed as waterproofers but do not effectively complete the job. Silicates are known densifiers; however if the sealer is a silicate/siliconate blend you are in luck since the smaller silicate molecule will densify and the larger siliconate molecule will chemically react and waterproof your basement. Silane/Siloxane sealers are excellent choices for basement concrete block and/or cinderblock walls. They are really the only effective solutions for waterproofing basement concrete block and cinderblock walls. And whatever you do, despite their claims, do not use DryLok to waterproof your basement. You will have numerous and countless adhesion problems since DryLok is latex based.
Our Take: Some excellent products on the market include Okon’s S-40, Diamond Hard and Lithi-Tek 9500