Restoring Old Concrete Patios: Tips For A New Look

If you're looking to restore an old concrete patio, there are several options to consider. Firstly, it's important to assess the condition of the concrete and identify any cracks, stains, or uneven surfaces. Depending on the extent of the damage, you can choose from various repair methods, such as cleaning and resealing, patching cracks, resurfacing, staining or painting, overlays, repairing edging, levelling sunken concrete, or adding decorative features.

One popular option is to resurface the concrete patio, which involves applying a thin layer of concrete to create a smooth and even finish. This can be done using a concrete resurfacing kit, which offers an affordable and easy solution. However, it's crucial to properly prepare the concrete patio by cleaning, patching, and priming the surface before applying the resurfacing material.

Alternatively, you can opt for more straightforward solutions, such as cleaning and sealing the concrete or patching cracks and holes with a concrete patching compound. If you're looking for a more creative approach, consider staining or painting the concrete to give it a fresh new look.

Before starting any restoration project, it's essential to understand the cause of the deterioration, which could be due to harsh weather conditions, heavy foot traffic, improper installation, or chemical spills. By addressing these issues, you can ensure the longevity and functionality of your concrete patio while enhancing its appearance.

Clean and seal the surface

If it has been a while since you last cleaned your patio, the surface will likely be covered in built-up dirt, mould, and other stains. To clean the surface, you can use a pressure washer to remove the grime and kill any mould. You should wear protective gear such as heavy boots and glasses during this process.

Once the patio is clean, you can protect it with a concrete sealer. There are two types of sealers: penetrating sealers and topical sealers. Penetrating sealers bond with the concrete to create a hydrophobic water barrier, protecting the concrete from mould, dirt, and water damage. Topical sealers, on the other hand, come in a variety of finishes and colours.

Sealing the concrete can be tricky if you are doing it yourself, so be sure to watch and read plenty of tutorials before you start.

Level uneven slabs

If your concrete patio has sunken or settled, there are several ways to level it again. Here are some methods to consider:

Concrete Levelling

This method involves drilling small, strategically placed holes through the uneven concrete slabs and pumping a compound beneath the surface. This compound fills any voids under the slab and gently lifts it back into place. It then hardens and provides a durable new base for the slab to rest on. This method can be used both indoors and outdoors and can save up to 70% of the cost of replacement.

Grinding

Grinding down the uneven concrete slabs is one of the cheapest and fastest ways to level your patio. However, it does come with some risks. Grinding will leave a splotchy and discoloured surface and will open up the absorbent pores of the concrete, making it more susceptible to damage during freeze-thaw cycles. It will also make the slab's structure thinner and weaker. Therefore, this method is only recommended as a temporary fix if you plan on replacing your concrete in the near future.

Add New Concrete or Patch Compounds

You can add additional concrete or patching compounds onto the uneven surfaces to even out the difference. You can buy concrete patch kits from hardware stores to fill smaller trip hazards and missing pieces of concrete. However, this method usually provides only a temporary solution as the new concrete will likely chip or crack off as the existing concrete expands and contracts.

Polyurethane Foam Injection (Polyjacking)

Small holes are drilled into the sunken sections of the concrete slab, and expanding polyurethane foam is injected into them. As the foam fills the space below, it lifts the slab until the uneven section is levelled with the rest of the concrete. This method is fast, non-toxic, and simple. It is also cheaper than replacing the entire slab. Once the foam has cured, you need to wait at least 15 minutes before walking or driving over the concrete.

Resurfacing

If your concrete patio is in relatively good shape, with only minor cracks, chips, or discolouration, you can consider resurfacing it. This involves cleaning and prepping the concrete, applying a bonding agent, mixing and applying the resurfacing material, and then applying a finish and sealer. You can choose from various resurfacing options, such as stain, micro-topping, stencil, or stamped concrete overlay. Resurfacing can be done as a DIY project or by hiring a professional.

Remove tree roots

Removing tree roots from underneath a concrete patio can be a challenging and time-consuming task. Here is a step-by-step guide to help you through the process:

Step 1: Assess the Situation

Before starting any work, it is important to assess the extent of the problem. Are the tree roots causing significant damage to the concrete? Are they affecting the stability of the patio? If the concrete is already badly damaged, it may be best to simply remove it and start fresh.

Step 2: Gather the Right Tools and Materials

Renting or purchasing the necessary tools will be essential for this project. You will likely need a jackhammer to break up the concrete, a saw to cut through the roots, and a trailer to haul away the debris. You will also need fill dirt to replace the removed roots and a plate compactor to ensure a solid base.

Step 3: Break Up and Remove the Concrete

Use the jackhammer to carefully break up the concrete patio, taking care not to damage any surrounding structures. Remove all the broken pieces and set them aside for disposal.

Step 4: Cut and Remove the Tree Roots

Once the concrete is removed, use the saw to cut through the tree roots. Try to cut as close to the tree trunk as possible to remove as much of the root system as you can. Remove the roots and dispose of them properly.

Step 5: Prepare the Base

Fill the area where the roots were removed with fill dirt. Use the plate compactor to ensure that the base is solid and level.

Step 6: Re-Pour the Concrete

Now it's time to re-pour the concrete for your patio. Buy enough concrete mix to cover the area and consider using wire mesh to reinforce the new slab. Mix the concrete and pour it into the prepared area, making sure it is level.

Step 7: Finish the Surface

Once the concrete is poured, finish the surface to your desired smoothness. If you plan to lay pavers on top, the finish does not need to be perfect, but it should still be reasonably level.

Removing tree roots from under a concrete patio is a challenging task, and it may be wise to consult a professional for advice or assistance before beginning the project.

Caulk concrete joints

Sealing the concrete expansion joints is crucial for maintaining the longevity of your concrete patio. These joints allow for the natural movement of concrete slabs, preventing cracks and breaks. If left unsealed, these joints can lead to issues such as sinking, settling, weed growth, and cracking due to freeze-thaw cycles.

Step 1: Prepare the Joints

Use a utility knife to remove any old sealant and clean off any remaining residue. To ensure a proper seal, clean the joints with acetone. This will help the caulk adhere better to the concrete.

Step 2: Insert a Backer Rod

After preparing the joints, insert a closed-cell foam backer rod into the gaps. This will fill any space and reduce the amount of caulk needed. Make sure the backer rod is slightly larger in diameter than the joint. It will provide support and prevent the caulk from sinking too far into the joint.

Step 3: Choose the Right Caulk

When choosing the right caulk for your concrete expansion joints, consider the width of the joint, the desired finish, and the climate conditions. Flexible non-sag and self-leveling caulk are the best options for sealing expansion joints. Self-leveling caulk is thin and fluid, making it ideal for filling smaller joints that require a smooth finish without manual smoothing. On the other hand, non-sag caulk is thicker and easier to control, making it a better option for joints that are over 1 inch wide.

Step 4: Apply the Caulk

Load the chosen caulk into a caulking gun and cut the tip of the tube to create a 1/4-inch bead. Apply the caulk into the joints, ensuring it fully fills the gaps. For self-leveling caulk, seal off any large gaps or spaces to prevent leaks.

Step 5: Smooth and Cure the Caulk

Smooth out the caulk using a spray bottle filled with soapy water, your finger, or a trowel for non-sag caulk. This will create a clean and professional finish. Allow the caulk to cure according to the manufacturer's instructions before driving or exposing it to water. This will ensure the longevity and effectiveness of the seal.

Resurface the concrete

Resurfacing your concrete patio can be a great way to give it a fresh, new look without breaking the bank. Here's a detailed guide on how to resurface your concrete patio:

Clean and Prepare the Concrete Surface:

Start by thoroughly cleaning the concrete surface to remove any dirt, grime, mildew, or algae. You can use a gas-powered pressure washer with a 25-degree fan tip and hold it 6-8 inches from the surface for effective cleaning. Make sure to wear protective gear, such as heavy boots and eye protection, during this process.

Patch and Repair Cracks and Holes:

After cleaning, inspect the concrete for any cracks, holes, or divots. For larger cracks and holes, use a concrete patching compound specifically designed for outdoor use. Fill in the cracks and smooth them out with a trowel. Allow the patches to dry completely before proceeding to the next step.

Choose a Resurfacing Product:

There are various resurfacing products available, such as concrete resurfacing kits, micro-toppings, stamped concrete overlays, or epoxy paint. Consider the condition of your concrete and your desired outcome when choosing a product. Some products may require the application of a bonding agent to ensure proper adhesion.

Mix and Apply the Resurfacing Material:

Follow the manufacturer's instructions for mixing and applying the resurfacing material. Work in small sections, as concrete resurfacing products can set quickly. Use a trowel or a gauge rake to spread the material, aiming for a thickness between 1/8 inch and 1/4 inch. If desired, use a broom to create a slip-resistant finish.

Apply a Sealer:

Once the resurfacing material has dried, consider applying a concrete sealer to protect the surface and enhance its appearance. Choose a sealer based on the desired finish, such as a penetrating sealer or a topical sealer. Follow the manufacturer's instructions for application, and allow adequate drying time before using the patio.

Maintain and Enjoy Your Refreshed Patio:

Your resurfaced concrete patio will require some maintenance to keep it looking its best. Clean and reseal the patio every 2-3 years, or more frequently if needed. Enjoy your refreshed outdoor space, which will now have enhanced curb appeal and functionality!

Frequently asked questions