A garage floor sealer sounds simple enough when you want to seal the concrete in your garage, but did you know that they come in two categories; topical sealers, such as epoxy, paint, and acrylics, and then penetrating sealers. Which do you choose? What are you trying to accomplish? Which is best for your application? Getting bewildered yet? Don’t worry, it’s not as confusing as it might seem at first.
Many times when someone is deciding on sealing the concrete in their garage, they are working on the premise of protecting the bare gray concrete for a nice clean look at the most economical cost. However, the many colored epoxy and paint coatings available on the market today are technically sealers as well. We will look at the different type of garage floor sealers available, discuss their properties, and determine how they will work on your garage floor.
Topical Garage Floor Sealers
Topical sealers adhere to the surface of the concrete. Known as film forming sealers or floor coatings, the most economical of these are acrylic. Most acrylic sealers are clear and form a thin protective layer on bare concrete. They are very easy to apply using either a pump sprayer or rollers, with two coats applied for the best protection. They will protect the floor from water and chloride intrusion, and give moderate protection against oil stains, vehicle fluids, hot tire pick up, and road salt if cleaned up fairly quickly.
Acrylic sealers can also enhance the look of the floor in your garage by giving it a somewhat wet, glossy look or you can opt for a less flashy matte finish. Once applied it will dry to the touch in a few hours. It can be driven on the next day and sometimes sooner depending on weather conditions at the time of application. Look for an acrylic sealer with UV protection if you have parts of your garage floor that is exposed to sunlight because it can yellow over time.
Though they are the least durable of the topical sealers, they stand up well to light traffic and need to be reapplied once every 18 to 24 months. For a more durable alternative, we recommend looking into the newer acrylic/epoxy hybrid sealers. These have endurance properties similar to epoxy but are applied like acrylic.
The next choice in topical sealers is epoxy. Being one of the more popular garage floor coverings, epoxy creates a cross linking adhesion in the coating due to the chemical bonding it provides. This makes epoxy sealers a much thicker coating than acrylic and very durable, but they are more difficult to apply. They require thorough concrete preparation, they are time sensitive during application, and must go on using rollers.
Epoxy sealers can withstand heavy traffic and are abrasion resistant. They are also resistant to water, most chemicals, oil, vehicle fluids, road salts, and hot tire pick up. It’s generally not a problem if you are slow to clean up any oil or fluids from your car that usually stain concrete. When you do clean, they will wipe right up and all the floor needs is mild soap and water to clean.
Care should be taken when it gets wet because an epoxy sealer can be a little slippery if not put down with any anti-slip agents. Epoxies are available in a clear coat as well as pigmented finishes and have a glossy shine that will enhance any color in the concrete. They are susceptible to UV rays however and can yellow if exposed to sunlight. A good quality epoxy coating can last for years on your garage floor.
Many of the garage floor coating systems today are made with a combination of layers of pigmented and clear coat epoxy to give a garage floor a very durable, chip resistant finish that will last many years. If that’s not in the budget, then a simple clear or pigmented coat on your floor will still give you greater protection for a longer period of time compared to acrylic sealers. Dry time is usually 18 to 24 hours and you have to wait 48 to 72 hours depending on temperature before you can drive on it.
Next on the list of topical sealers is polyurethane. Polyurethane has many of the same properties as epoxy and is even more durable. It also has the added benefit of being resistant to UV rays. So if you have a garage floor that is exposed to sunlight you don’t have to worry about it turning yellow. It used to be that polyurethane was only used as a clear coat sealer, but that is slowly changing however with manufactures starting to offer it in colors. One thing to keep in mind is that polyurethane does not bond well to bare concrete and usually needs a primer such as epoxy applied first. You also have a choice of finish from matte, to semi-gloss, to glossy.
Like epoxy, most polyurethanes can be slippery when wet. Because they have a thinner film thickness than epoxy, polyurethane makes for a great top coat to apply an anti-slip agent. Application difficulty and dry time is similar to epoxy as well. Though it is a little more expensive than epoxy, polyurethane may be what you need if you have a garage floor that is exposed to sunlight and you want something other than a glossy finish.
Last on the list is the newer polyurea and polyaspartic floor sealers. These are a sub group of polyurethane and have a similar finish to epoxy coated floors. Unlike epoxy and polyurethane, these coatings can be applied in extreme temperatures from below freezing to over 100 degrees and have extremely fast return to service times. You can actually drive on them the next day.
Penetrating Garage Floor Sealers
Penetrating sealers is the next category in concrete sealers for a garage floor. There are four different types of penetrating sealers for concrete, but only two need be discussed for a garage floor.
The first of these is a siliconate sealer. Though this kind of sealer is used extensively for exterior concrete such as sidewalks and driveways, it will work just as well in your garage if you just want to seal the floor without changing the way it looks. It works by penetrating into the upper surface of the concrete and reacting with free lime. This will form a calcium silicate that essentially strengthens the concrete by filling pores and prevents liquids from migrating through.
This process works to help prevent freeze-thaw damage and deterioration due to corrosion. It has a matte finish that doesn’t change the appearance of the surface because it penetrates the concrete. It’s easy to apply using a pump sprayer or rollers and generally only needs one coat. Some of these sealers are expected to last 20 years or more.
The second choice that is being used among the bare concrete purists is a concrete densifier or densifier and sealer combination. Used primarily for polishing concrete and adding strength to newly poured concrete, these sealers are being used more on garage floors by people looking for a no nonsense simple solution that will prevent dusting and harden the surface of a working garage as well as repel liquids.
One thing to keep in mind; if you have small issues with moisture coming through the concrete, a penetrating garage floor sealer is a good choice to consider. Because they work by filling the concrete pores, they do well for blocking moisture coming up from underneath your slab. If you like the finish of acrylic sealers, make sure the solids content is not more than 25% and that it is not applied in more than two coats. This should be permeable enough to let the moisture transmit through the sealer.
Most epoxies and urethanes will not allow moisture transfer and will peel or damage the surface of the concrete. To see if this is an issue, you can test your floor by taping all four sides of a 12” square piece of clear plastic to your floor. Wait 24 hours to see if it has collected any water to the plastic. If it has, then you have moisture coming up through the concrete.
For more information about the durability of concrete sealers, here is a chart from the Concrete Network that compares sealers and what they do.
Depending on what you want your garage floor sealer to do for you, decide which product is best suited for your requirements and budget. Either way you choose, a good sealer will be a nice investment in the care and finish of your floor.