Concrete patios are ubiquitous due to their low maintenance and low cost. However, they also can get damaged and cracked over time, forcing homeowners to either fix the problem or install a new patio. The homeowner who wants to save money should obviously go with the first choice, but what concrete patio repair options are available? And how will the finished product look when compared to the original installation? Though you can hire contractors to do this work, it can be a easy DIY project for you to complete by yourself. Here is what you need to know about concrete slab repair:
Fixing Cracks in Concrete Patios
If you ever detect a problem with your patio, you need to jump on it immediately. Leaving it be will only make the problem worse. This is especially true with cracks, which may get wider over time.
The most common problem you’ll see in a slab is a crack. This will develop for a number of reasons, but the most common is due to freeze/thaw cycles. Water underneath the slab freezes and thaws; this action puts stress on the slab, leading to cracks and breaks. Even if rebar or wire mesh is put in the concrete, it may still crack, especially if you live in an especially cold environment.
The first thing you need to do is ‘diagnose’ the crack – how long, wide, and deep is it. If it is narrow and shallow, it is a “hairline” crack; if it is deep and wide, it a regular crack. The qualities of the damage will affect the kinds of repairs you’ll have to do.
You may also find that the surface of the patio is covered with webs of hairline cracks and other deformities. In this case, you’ll want to get resurfacing products that will create a new, thin layer on top of the concrete that will fill in and disguise the cracking.
Concrete Repair Products
Next, you need to choose what kind of product you’ll use to fill in the crack. Your choice will depend on the properties of the crack discussed above. There are two main kinds. The first is essentially remaking concrete without aggregate. This is a combination of Portland cement and sand which will create a liquid “crack filler” that you can use to fill in the crack. If the crack is relatively thin, you can also try using ‘epoxy’ fillers. If the crack is very wide, you may have to add aggregate to your Portland cement and sand mixture. Essentially, this would be putting fresh concrete into the crack.
You can also get concrete patching mix which can be used for flaking and more widespread damage. Check your local home improvement store for products that fit your need and budget.
Preparing for Concrete Floor Repair
Before attempting any repairs, make sure the surface of the patio, and the crack itself, is clear of any large or small debris – rocks, dirt, loose concrete, etc. Brush away any debris from the crack, and use a hose or pressure washer to clean and wet the crack thoroughly.
You may want to do some more prep work on the crack itself to help increase its adhesion to the new concrete patch. Use concrete adhesive or phosphoric acid to do this, especially for narrower cracks.
Using the Portland Cement and Sand Mixture
Make and use this mixture if the crack is thin (hairline), as the mixture will seep in to the area and help rebind the crack.
However, if the crack is very wide, you’ll have to add aggregate to help fill in the space and keep the newly filled area strong.
Before filling in a large crack, you may have to ‘undercut’ it, e.g. make it bigger at the bottom of the crack. This ensures that the repair will be most effective. To do this, simply use a hammer and chisel and remove some of the concrete near the bottom of the crack; the crack should then be wider at its base than the top. Then, when the concrete pours in, the repair will hold up better with the wider, stronger base.
Using Epoxy Filler
Use this product if the crack is one inch wide or less; it should also not be very deep. The color of the epoxy is usually grey to help match the cement. It is delivered in a caulkin tube; you’ll have to use a caulking gun to apply it to the needed areas.
When filling the crack with any material, make sure to fill the bottom first. Fill the crack to the brim, and then remove any excess, leveling off the patch in the process. Let it cure before walking on the area. Epoxy doesn’t need to be finished in any way, but you’ll want to cover the repaired area for up to five days. Wet the area every day as well during the curing process.
What About Other Damage?
Though cracks are the most common, there are other types of damages to patios as well. For example, holes and depressions may develop in the surface of the project. You can use many of the same products and techniques for these problems as with cracks – in a sense, treat them as very wide, short cracks.
However, some other problems may be more cosmetic and widespread than simply functional and limited. For instance, the surface of your concrete may begin to wear and look rough; this can bother you on an aesthetic level. One way to remedy this problem is to resurface the structure. You could also use concrete patio paint or finishes to give the surface a new face; if you want to get really aggressive, consider adding outdoor patio tile or thin pavers over concrete. There are many options available to you; the ones you select will depend on how you want the patio to look, how long you want it to last, your budget, and your tastes.
Note as well that you should seal your patio to help keep it smooth and in good shape for a longer period. It will prevent stains from setting in to the surface, which can be hard to remove, and can protect it from water and the elements. Buy a good concrete sealer and apply it as directed on the packaging.
Note that fixing this crack will not prevent further cracks from forming. You may have to consider installing a new patio type if you can’t control the cracking. You could consider using patio pavers, for example, to have a project that will resist freeze/thaw cycles.
Concrete patio repair is definitely feasible for many homeowners, especially if the damage is minimal. However, if the damage is severe or extensive, you may want to hire a contractor. If the job is done poorly, it may look worse than the crack did.