Resurfacing Concrete Patios: Top 'N' Bond Method

Resurfacing a concrete patio is a great way to give your outdoor space a new look. There are a variety of options to choose from, including staining, micro-topping, stencilling, or using a stamped concrete overlay. The process involves repairing any cracks, cleaning the surface, applying a bonding agent, mixing and applying the resurfacing material, and then finishing and sealing the concrete. While it is possible to DIY this project, it is important to properly prepare the concrete patio for resurfacing and ensure the existing concrete is in good condition. Otherwise, it may be more cost-effective to replace the concrete entirely.

Clean the concrete with a power washer

To clean concrete effectively with a power washer, follow these steps:

Firstly, clear the area of any loose material, such as stones, dirt, toys, bikes, and potted plants. You can use a leaf blower or broom to do this. If there are any walls or doors nearby, cover them with a tarp and some painter's tape to protect the finish. If there are plants growing in the ground close to the concrete, cover them with a tarp, but only for a short time, as tarps can limit their air supply.

Next, determine which end of the concrete is the highest, and the direction in which water flows when it runs across the surface. You should start power washing at the highest point, so the water will flow away from your work area.

Before you begin power washing, read the instruction manual for your model. Generally, you will need to connect the spray wand to the washer using a pressure hose, and the washer to a water supply using a garden hose. To apply detergent, use a low-pressure nozzle, and to rinse, use a high-pressure nozzle. Do not use a high-pressure nozzle on brick surfaces, and be aware that power washing can damage concrete, so test it on a small, hidden area first. The cleaning power of a power washer is determined by combining its water pressure (PSI) with the amount of water used (GPM).

When using a power washer, wear safety equipment to protect your eyes and ears, and always wear closed-toe shoes. Be extremely careful not to point the spray wand at other people, and keep yourself out of the path of the spray. Stay aware of your surroundings, and keep an eye out for children or pets.

Now, apply a degreaser to the concrete to loosen stains. You can use a tool attachment on your power washer, or scrub the degreaser into the concrete with a stiff-bristled brush or push broom.

Once you have applied the degreaser, start power washing at the highest point, pointing the spray wand at the concrete surface and pressing the trigger. Sweep the nozzle steadily back and forth across the concrete, overlapping each stroke by several inches.

After applying detergent to the entire surface, let it stand for around 15 minutes, rewetting occasionally to prevent it from drying out. Then, switch to a high-pressure nozzle and set the power washer to rinse mode. Repeat the sweeping pattern, washing away the detergent and using the spray to lift any remaining grime or stains. Make tighter sweeps to lift heavier stains, and be sure to rinse away all of the detergent.

Finally, allow the concrete to dry completely.

Apply a bonding agent

After the patches have dried for the amount of time recommended by the manufacturer, it's time to apply a bonding agent to the prepared concrete. Bonding agents are crucial in creating a strong bond between the old concrete and the new overlay material. Many of these agents contain latex and/or polymers to enhance this bond.

Typically, you can apply the bonding agent with a ⅜-inch nap paint roller. Be sure to carefully read the manufacturer's instructions, as some bonding coats should remain tacky when the overlay is applied. This step is relevant for stamped overlays and micro-topping methods that use a mixed cement-based overlay material to resurface the patio.

For example, if you're resurfacing a concrete driveway, this step would apply. It's important to ensure that the concrete is properly prepared before applying the bonding agent, as this will impact the durability of the new surface.

Mix the resurfacing material

Mixing the resurfacing material is a crucial step in the process of resurfacing a concrete patio. Here is a detailed guide on how to do it:

Before you begin, make sure you have the necessary tools and materials. You will need a five-gallon bucket, a power drill with a mixing paddle attachment, and the overlay mix. The overlay mix can be purchased as a dry mix, which you will need to combine with water, or it may come with other additives such as liquid or powdered pigments.

Once you have gathered the required materials, carefully read and follow the directions on the packaging. The specific mixing instructions may vary depending on the product you are using. Pay close attention to the recommended amounts of each ingredient and any specific mixing techniques that are advised. Some materials, for instance, should be mixed in a way that prevents air from being incorporated into the mixture, as this can create bubbles and voids that weaken the final product.

Now, you can begin the mixing process. Start by pouring measured amounts of the dry overlay mix into the five-gallon bucket. If your product requires the addition of water and other additives, add those as well, in the specified quantities.

Next, use the power drill with the mixing paddle attachment to slowly start blending the ingredients. Be sure to follow the recommended mixing speed and duration to ensure a thorough mix. The mixing process should be done carefully to avoid introducing air into the mixture, which can compromise the durability of the finished overlay.

It is important to note that reinforcement fibres should not be added to the overlay mixture. These fibres can protrude from the resurfaced patio, posing a safety hazard to bare feet or any skin that comes into contact with the surface.

By carefully following these steps and the specific instructions provided by the manufacturer, you will be able to effectively mix the resurfacing material for your concrete patio project.

Spread the resurfacer

Now that you've mixed the resurfacing material, it's time to spread it onto the concrete. Pour the mixed material onto the prepared concrete and spread it around with a trowel or a gauge rake set to the recommended thickness. The usual thickness for an overlay is from 1/4 inch to 3/8 inch, compared to how thick a concrete patio should be at about 4 inches.

If you're using stain or epoxy paint, apply it with a roller or sprayer, depending on the method recommended by the manufacturer. Work in smaller sections if the material sets up or dries quickly. Avoid "cold joints" by ensuring that you're applying fresh overlay material or epoxy to an edge that's already dried or set up. You want the resurfacing material to be one continuous surface without seams between sections.

If you're using a cement overlay, remember that concrete resurfacer sets quickly, so mix small amounts at a time and work in sections. Spread the resurfacer until it's between 1/8 and 1/4 inch thick. For a slip-resistant finish, wait five minutes, then sweep a nylon-bristle concrete broom across it, 90 degrees to the foot traffic.

Remove any weatherstripping after 20 minutes. Wait at least six hours before walking on the patio. Cover the patio only if rain is expected.

Apply the finish

Applying the finish to your concrete patio is where the artistry happens. Unless you have experience finishing concrete, it may be worth hiring a concrete finisher for the job. Mistakes during this part of the process can leave a lasting impression on the quickly hardening cement surface.

If you're applying a cement overlay, this is when you stamp the pattern in or apply a broom or swirled-trowel finish to give the overlay some texture for safety as well as aesthetics. An experienced cement mason will know tricks for quickly correcting any little accidents that can happen.

Epoxy paint usually does not need a clear sealer applied. But almost any other resurfacing material should be sealed with a type of concrete sealer designed for decorative concrete. You can tint sealer going over stamped concrete to provide contrast between the higher and lower areas of the texture and pattern for a more realistic look.

Pro tip: Mix a non-slip additive into the sealer so that the resurfaced patio is not as slippery when it’s wet. Sealer without this additive can be very slippery when wet.

Typically, you’ll apply at least two coats of sealer. Use a roller frame with a handle attached to it and a ⅜-inch to ½-inch nap roller cover. Dip the roller into the bucket of sealer and roll the first coat, allowing the recommended amount of dry time between the first and second coats.

It’s important to avoid getting water on the sealed patio within 24 hours of applying the sealer. Also, if possible, it’s best to avoid applying sealer when the temperature may drop below freezing within 24 to 48 hours, as freezing can interfere with the curing process and result in delamination and discoloration.

Frequently asked questions