Many factors determine whether or not a floor coating system can bond successfully to concrete. This includes the proper surface preparation.
A reliable epoxy flooring contractor will field test your slab to assess its readiness for the application of a new coat. They’ll often use a simple water drop test to determine if concrete is ready for epoxy.
1. Check for Moisture
Moisture is one of the biggest problems that can threaten a concrete floor epoxy coating. This unseen issue can cause everything from mold to a failure of the entire floor. Moisture can come from many sources. It can be released from new, freshly poured concrete, or it can leach from water in the ground below. It can also be pushed up through the concrete by hydrostatic pressure. Regardless of where it comes from, moisture must be dealt with to ensure a good epoxy finish.
The problem is that concrete is a very porous material, with millions of tiny channels and voids. These tiny pathways are perfect for migrating moisture and water vapors to travel through the slab. This is a serious threat to epoxy, as it cannot bond properly with wet materials. Moisture can even cause structural damage to the concrete itself, if it’s allowed to penetrate deep enough.
So how can you tell if your concrete has excess moisture? It can be hard to see if there is moisture present in the concrete, as it may lie below the surface. However, there are a few signs that you should look out for:
You might notice that some parts of your concrete are darker or damp. Efflorescence is another sign of moisture, as it’s created by concrete absorbing water and then evaporating. It leaves behind a white powdery residue on the surface of the concrete.
If you notice that part of your concrete has more moisture than others, or if you see a powdery residue, it’s important to conduct a thorough concrete moisture test. There are many different ways to test for moisture in concrete, but the most popular is to use a moisture meter. These are small handheld devices that can be used to measure the moisture content of a concrete surface. They are very affordable, easy to use, and effective at measuring a wide range of moisture levels.
Other testing methods include calcium chloride testing and relative humidity testing. These more destructive tests involve inserting a small container that absorbs moisture into the concrete, then weighing it before and after. While they require more time and effort, they can give you a more precise moisture reading than the less expensive moisture meters.
2. Check for Defects
Concrete is a material with many different defects that can appear during the mixing, placement and curing process or after construction. These include cracks, chips, spalls and holes. These may be the result of chemical reactions or natural weathering and aging. They can cause structural damage to buildings and structures and be hazardous for occupants.
If a floor has surface imperfections, it must be repaired before an epoxy coating can be applied or customized to match your existing décor. This isn’t just for aesthetic reasons, it’s essential to ensure the longevity of the epoxy flooring. Uneven or chipped surfaces will allow water and moisture into the concrete, which can cause problems later on. It’s important to choose a quality product that is designed to be applied over these types of surfaces.
When an experienced contractor prepares a concrete floor for epoxy, they will carefully examine the surface to make sure it’s ready for the application of the main coating. This will include a thorough inspection for dirt, mildew, grease, oil residues, rubber residues and any other materials that can interfere with the bonding of an epoxy surface to the concrete. The concrete must also be dry.
Some floors will require acid etching to create a rough, porous surface that will enable an epoxy coating to bond properly with the concrete. This is a complex and time-consuming procedure. It’s not recommended for DIY projects. It’s important to follow the instructions that come with the specific acid etching product being used.
Other prep steps may be more involved and involve blasting or scarifying the concrete to remove any contaminants or to make it smooth enough for an epoxy coating to adhere properly. JEP Epoxy Floors uses multiple methods for this, including shot blasting, which creates a three-times smoother surface than grinding; and scarification, which impacts the concrete’s surface at just the right angle to strip away the top layer of concrete.
If the concrete has been prepared properly, it’s then ready for a primer to be applied. There are a wide variety of quality primer products on the market. An experienced contractor will know what type of primer is needed for the project at hand.
3. Check for Cracks
Whether your concrete floor is brand new or old, it will likely be cracked in some areas. If this is the case, you can repair these cracks using a variety of methods depending on their severity and what the concrete was used for. Cracks are common in concrete but they do not have to be permanent if the cracking is due to external pressure or environmental conditions and can be repaired by injecting, grouting or other appropriate materials.
The key to successful epoxy application is in the preparation of your concrete substrate. The concrete must be free of dirt, oil, wax, dust and mildew. It must also be rough rather than smooth so that the epoxy can bond to it. This can be accomplished by grinding or acid etching the concrete.
Before beginning to prepare your concrete for epoxy, make sure you cover any walls, windows or shelving in the garage with tape and plastic sheets to protect them from damage by the dust generated by the grinding process. It is also important to protect yourself from the dangerous fumes produced by the muriatic acid etching solution. This chemical is very corrosive and can eat through almost anything it touches, including your clothes and metal and can cause a lot of harm to your lungs and nasal membranes if inhaled.
Once you have protected your surfaces and completed any necessary repairs, the next step is to clean your concrete floor. This may involve removing oil spots, cleaning/degreasing the entire surface and scrubbing or vacuuming thoroughly. Then you should rinse the concrete completely to remove all chemicals, dust and soap.
If the concrete slab has not yet cured, it must be allowed sufficient time to do so. The industry rule-of-thumb is 30 days for each inch of slab thickness. Excess moisture content in a concrete base is the surest way to ensure that any subsequent epoxy flooring will fail prematurely. This is why we recommend using Wagner’s Rapid RH relative humidity testing to assess concrete slab moisture content before beginning your project.
4. Check for Stains
If your garage floors are stained, you’ll need to clean them before applying the epoxy. Stains can inhibit proper bonding between the concrete and the epoxy, so it’s important to remove them completely. This process can take a long time and will require a lot of work, but it’s essential for the success of your epoxy floor. You’ll need to use a high-powered degreaser to remove grease, oil, wax, and mildew from the concrete. Be sure to wear eye protection and non-absorbent gloves when handling the chemicals used in this step.
Once you’ve scrubbed the concrete, rinse it with water. Then, test the concrete’s readiness for staining by pouring a small amount of water on the surface. If the water absorbs within 5 minutes, the concrete is ready for staining. If not, the surface will need further preparation such as etching with CitrusEtch Concrete Etcher.
Before choosing a colorant, make sure that it is compatible with the concrete type. There are two types of stains available: acid-based and water-based. Both will offer different aesthetic results, but the main difference is that acid-based stains react with the chemical compounds in concrete to create a permanent bond. This makes them long-lasting and resistant to fading. Water-based stains, on the other hand, create a more opaque finish.
Staining the concrete isn’t a simple task, and it’s important to follow all instructions on the product packaging carefully. You’ll need to prepare the area for staining, including covering walls, furniture, and any storage shelves that touch the floor. Be sure to wear all appropriate safety equipment, and always test a small patch of stain on the floor before using it. You’ll also need to let the concrete dry thoroughly afterward, depending on the type of stain and environmental conditions.
If you’re working with an acid-based stain, it is crucial to maintain adequate ventilation throughout the project. This will protect you from the fumes, which can irritate your nose, mouth, and eyes. You should also be sure to use a mask when working with acids, as they can eat through metals and the lining of your lungs.
