A new trend that is slowly working its way into the garage is the use of a concrete densifier sealer on the garage floor. Densifiers have been used on occasion in the garage for a variety of reasons, but rarely as an actual finished garage flooring treatment. So why has there been a gradual increase in its use and popularity for the garage floor?
The reason is the addition of silicone and siliconate agents in some densifiers to act as a sealer. This helps to create not only a water repellant floor, but one that is resistant to liquids in general. So let’s take a closer look at how a concrete densifier with sealer on your garage floor may be beneficial for you.
How a concrete densifier works on a garage floor
Concrete densifiers have been around for decades. They are a concrete hardener and in the flooring industry used primarily for concrete floor polishing, abrasion resistance, anti-dusting, and in some cases to harden softer concrete surfaces before grinding.
Lithium densifiers are the most common choice used for garage floors. This is due to their ease of application and less reactive properties to carbon dioxide which can create a whitening effect on the floor. Unlike sodium densifiers, lithium densifiers also do a good job at repelling road salts. Once applied, the concrete retains its natural matte look.
When concrete cures, bleed water makes its way to the surface increasing the water to cement ratio, laitance content, and fine aggregates. This is what helps to make the surface of concrete smooth, but it also creates a surface that is softer than the underlying cement. When a densifier is introduced, the chemical reaction increases the surface strength of concrete from an average of 20% to 40% depending on the original pour and finish of the concrete.
It does this in two ways. The densifier is a water based chemical solution that first works by penetrating into the surface of the concrete and reacting with calcium hydroxide to produce calcium silicate hydrate (CSH). This is the substance that gives concrete its strength. Next, the CSH that is produced fills the open pores of the concrete increasing its density.
It’s important to note that concrete densifiers are non-film forming, meaning that they don’t leave a topical film on the surface to protect it from liquids and staining. This is why they haven’t been used much as a finished product for garage floors – until recently.
The addition of silicone and siliconate agents in densifiers creates a waterproofing agent right at the surface of the concrete. This allows the concrete densifier to act as a sealer for your garage floor by repelling water, oils, chemicals such as road salts, and other fluids. They can also be used over stained concrete.
Are they 100% impervious to stains and chemicals? No, but if you don’t allow spills to sit for a long period, they will generally wipe right up with little if any scrubbing necessary. Be particularly careful with solvents that can stain, as their resistance to them is minimal.
The benefits of a concrete densifier with sealer include:
- Added strength and abrasion resistance to the surface of a working garage
- Increases the compressive strength of concrete
- Repels liquids and other fluids which help to make your garage floor stain resistant
- Helps to bring color out of stained concrete
- Eliminates dusting and problems with efflorescence
- It doesn’t peel, leave tire prints, or turn yellow
- Helps act as a moisture barrier for your garage floor
- Improves weathering and resistance to freeze/thaw effects
- Non-slip surface
- Relatively inexpensive
- Easy to apply and is ready for traffic within an hour or two
How to apply a densifier to a garage floor
The application of a densifier sealer for your garage floor couldn’t be much easier. You first need to make sure your garage floor is clean and free of all dust, oils, and foreign contaminants. Any stains that you may have will essentially be locked in unless removed first. The surface must be completely dry before applying the product and most manufacturers allow for you to use a pump up sprayer, rollers, or mop for application.
Once applied, the product needs to sit for 20 to 30 minutes without drying out. You can mist a little water on the surface if necessary to keep it wet. Once this time period has elapsed, you can mop up any excess or hose it off with a mild detergent or just plain water depending on the product. You then wait for an hour or two for the floor to dry and you are ready for traffic. That’s it. One application is all that is required.
One note to make is that if you plan on adding a topical coating such as epoxy at some point in the future, the densifier will not interfere. You will still need to grind your floor to create a mechanical bond however.
Just remember, if you are looking for the similar protection of epoxy or some other multi-stage coating, then this type of product isn’t for you. If you like the look of bare concrete and have a working garage or pole barn that you want to protect without making a big project out of it, then a concrete densifier sealer applied to your garage floor may be just what you are looking for.