How to Repair Cracks in Concrete Before Epoxy Coating

Steps to Fix Cracks on a Concrete Surface Before Applying an Epoxy Coating

Concrete surfaces can be beautifully and durably transformed by the addition of epoxies. Pre-pour eroding prep work is equally, if not, more important as touch up work ensures a sturdy attachment and beautiful finish. Through my experience, as an epoxy floor specialist, ample time spent troubleshooting concrete flaws drastically improves end results. In this guide, I explain how one goes about filling up concrete flaws before applying toppings.

Evaluating Cracks in Concrete

As with everything, the most important step is the very first one – in our case, figuring what concrete cracks we are dealing with. Cracks come in diverse shapes and sizes, hence, one must first note down all the crucial factors before proceeding on fixing the gap. The width and the depth of the gap are the two most vital criteria that will allow you to properly fix these cracks. Concrete cracks that bulge out and sit on the floors use different techniques as cracks that just barely break the concrete surface.

As stated, the most common type of split is the one with ultra thin fissures that sit at the body of the block on each side.

Always clean the area to verify the size and depth of the cracks. Use a vacuum or a wire brush to view the surface better. Make sure to check for any moisture intrusion. Damp areas could indicate bigger problems such as a leaking pipe or poor drainage.

Make sure to analyze the location of the cracks too. Cracks located on high traffic parts of the structure like driveways or garage floors may require more extensive techniques for enduring the pressure and weight they will experience. If you estimate the cracks to be major or out of your capabilities to fix them, you should seek out advice from a structural engineer or a specialized individual to assess it properly.

In the case of cracks that have uneven surfaces or can be moved when force is applied on them, repairs should be made using leveling compound first. Also, remember to look for expansion joints located in the structure. These gaps in the concrete, designed to facilitate movement, should not be mistaken for spaces that need repair.

Finally, observe the development of cracks for any other patterns. A consistent pattern might point to a common cause, like settling or expansion due to heat changes. Knowing why the cracks occur will assist you in selecting appropriate repair methods and avoiding further damage. For more information on assessing cracks, this guide contains in-depth material that may be helpful.

Tools and Supplies Needed for the Repair Task

In order to complete the repairs for the cracks in the concrete, you will need to possess proper tools and materials for all the necessary steps in the repair procedure. You will first list common household items before moving on to more specialized tools. To get you started, I have included the items you need to gather.

Wire brushes or a scraper for cleaning

A vacuum or air compressor for dust removal

A chisel and hammer to widen gaps smaller than the blade width

Filler applicator

Sealant expander

You will be required to choose from either epoxy putty or patching compounds depending on the size of the cracks you are dealing with. They will merge with the concrete quickly, creating a strong bond, which is exactly what you want for durable repairs. A liquid filler may be a better choice for minor and narrow gaps because of its ability to seep into small spaces.

In order for the repair epoxy, bonding glue and primer, to hold properly onto the concrete structure, you will need to first fulfill the requirements for the building materials. This is highly essential in cases of the bigger cracks or if the concrete has the possibility of being exposed to water. Make sure the product you choose does not interfere with the coating epoxy you plan to use after.

First, safety equipment is equally as vital. It is recommended to wear gloves, goggles, and a dust mask to shield yourself from any and all dust and debris while performing the repairs. Concrete dust may be harmful to one’s eyes and lungs, thus, precautions need to be made.

As a final step, make sure you check the instructions of all the products to guarantee their combination and best usability. Most of these tools and materials are available at a nearby hardware shop or even on the internet. For example, Home Depot has numerous concrete repair products that are conveniently available for delivery.

Washing and Getting Ready the Cracked Surface

Cleaning and preparing the surface is a crucial step that one must complete before filling patching concrete cracks. A good cleaning beforehand gives a higher opportunity of adhesion and provides a reliable and lasting seal. Here’s how effectively prepare your concrete surface.

Remove any loose dirt, debris, and dust from the crack and the area surrounding it. A wire brush or a scraper can aid in getting those particles trapped in the crack out. Ensure that the surface is as clean as possible so the repair solution has the best chance of bonding with the building material. Moreover, a vacuum or an air compressor works wonders when it comes to blowing out leftover dust or debris.

With the chisel and hammer, widen the crack a bit with care. It might seem like a losinger approach, but it does make the repair stronger by giving the repair material more surface area to stick on to. Be careful so that you do not further damage the surrounding concrete during the process.

Now, after cleaning the crack, applying the bonding adhesive is next. The adhesive acts as a primer to make sure the filler or epoxy used later in the steps bonds strongly to the concrete. Use a brush to spread it on and leave to dry as commanded by the manufacturer. For larger cracks or cracks on surfaces exposed to water, this is a crucial step as it makes the repair stronger and more reliable.

Think about adding a foam backer rod for deeper and wider cracks before adding the filler. This makes the filler more stable while using less of it. Rods add value especially to vertical surfaces where the filler would sag during the application.

Make sure to also scrub the surrounding concrete area. The process of bonding and repairing would be compromised if contaminants like grease and oil is present. Adequate rinsing must be done after applying a degreaser or cleaner.

Ensure the area is still void of liquid before proceeding to the next step. Any water left over in the surface can damage the repair, so ensuring it is perfectly dry prior to work is essential. For additional surface preparation tips, visit our dedicated guide on preparing surfaces.

Techniques in Filling and Sealing Cracks

After the area has been cleaned, the next task is to fill and seal the designated cracks which are best done using different methods per the size and type of cracks.

Using liquid concrete fillers works best on fine hairline cracks. These types of fillers are manufactured to fill even the tiniest holes which guarantees excellent adhesion and a level surface. Start by pouring the crack filler into the void and use a putty knife afterward to scrape away the leftover material.

When it comes to large or major cracks, it is preferable to use an epoxy or polyurethane based repair product. These materials have great strength and flexibility which is best for cracks that are likely to undergo expansion or contraction. Follow the guidelines of the manufacturer when mixing the epoxy and apply it on the crack with a putty knife. Ensure that all the voids are completely filled without any air pockets and the surface is level.

Use a sand or backer rod as a filler for the cracks. It helps decrease the amount of repair material. Use a wide combination of techniques for deep or wide cracks. Finally, cover the gap with epoxy or filler for a long lasting seal.

For repairs that are overhead or vertical use non-sagging formulas. These products remain at the spot they are applied and do not drip or run the material that could damage the repair.

Moisture can cause severe damage to concrete, thus sealing the repair is extremely important. Fill in the cracks and cover them using a concrete sealer or epoxy primer. This enhances the life of the repair while simultaneously ensures quality of work.

Before advancing to the next stage, ensure that the repaired areas are cured fully. Different curing times for various products have to be observed – refer to the manufacturer’s guidelines for instructions. For steps with more details or images, please visit our repair techniques resource.