There are two possible reasons why you might need to resurface a concrete patio:
- The concrete has deteriorated slightly over time (but is still structurally sound) and you wish to give it an aesthetic makeover. Resurfacing is a job meant to deal with discoloration or tiny cracks; if your patio is structurally compromised, you will need to replace it.
- You want to raise the level of your patio surface slightly where it meets a driveway, walkway, etc., so that it will be flush with it. Unevenness where the two surfaces meet can make your yard unsafe, creating a tripping hazard. In addition, water runoff from the sunken patio surface could eventually undermine the driveway or walkway by seeping under it.
This is a fairly easy do-it-yourself project for beginners. It will require about one hour of your time per 5 square feet of surface to be covered.
Supplies Needed, Tips to Get Started:
- QUIKRETE Concrete Resurfacer (or the equivalent)
- Masonry trowel
- A container within which to mix the concrete resurfacer (such as a wheelbarrow)
- An instrument with which to stir it (such as a shovel)
- Duct tape
- Water supply (for example, a garden hose)
- Protective clothing (especially gloves)
- Safety mask and goggles
- Optional: broom, concrete float
- To rent: power washer
Buy a product specifically designed for resurfacing concrete. QUIKRETE Concrete Resurfacer is an example of a product intended for precisely such thin applications. Its composition (primarily Portland cement, sand, and polymer modifiers) is such that the shrinkage resulting from the drying process is reduced. This quality makes it ideal for thin repairs. When resurfacing concrete to a depth greater than 1/2 inch, make successive applications (allowing for drying in between).
It is impractical for the average homeowner to buy a power washer, since the use that you would get out of it would not justify the cost. Luckily, power washers are readily available at your local rental center.
Instructions for Resurfacing a Concrete Patio:
- Wash the existing concrete surface with a power washer. This step will help the new concrete adhere to the old surface.
- You do not want to fill in your existing control joints, so apply duct tape over them. Likewise, mask any other contiguous surfaces to keep them clean.
- If, by the time you get ready to apply the new concrete, the surface you power-washed has dried, thoroughly wet it again, to improve adhesion (but there should be no standing water).
- Mix the new concrete. The most basic way to do so is in a wheelbarrow, using a shovel.
- Properly mixing concrete involves adding water in stages, until the proper consistency is attained. In most cases, you will add the water using a garden hose. However, if you are resurfacing your concrete patio on a cool day and the surface area that you need to cover is fairly small, you can bring out heated water from your house to speed the setting time.
- Shovel the new concrete onto the surface, and spread it with your masonry trowel.
- If your concrete resurfacing needs to be ultra-smooth, run a concrete float over the new surface before it hardens (this is feasible if you treat only one small area at a time).
- To make your resurfacing more slip-resistant, run a broom across it before it hardens.
Curing the Concrete:
- Drying time is about six hours, at minimum (meaning no one should be allowed to walk on the patio during this time). But wait 24 hours before driving a car onto your patio.
- Temperature is a factor in the curing (drying) process. The colder it is outside, the longer it will take for the concrete to dry.
- Rain is your enemy in this project. If rain is in the forecast, cover your concrete patio with a sheet of plastic for at least six hours. If rain is projected and it is cold outside, keep it covered for even longer.
- There is no need to apply a sealant to the surface later.
One of the key jobs to research as preparation to resurface a concrete patio (or for any project involving concrete) is curing concrete properly. You could do everything else right, and yet, if you were to get this one step wrong, your whole project could be ruined.