Sealing driveway cracks as soon as they appear prevents them from getting worse and more difficult (and expensive) to repair. Sealing driveway cracks is a fairly easy job that you can do on your own (with a few exceptions). Below is a guide on the best driveway sealer for cracks and how to go about sealing driveway cracks.
What You'll Learn Today
Why Is It Important To Seal Driveway Cracks?
That small crack on your driveway may not seem like a big deal, but it’s the start of more damage that’s to come.
What happens is that water settles in the crack. As it freezes and thaws, it expands and contracts. These movements gradually widen and lengthen the crack. As more water gets in, the crack grows faster.
The water also affects the strength of the underlying base material, further weakening the driveway. This can introduce more cracks as well as potholes and sinkage.
That’s why it is important to seal a driveway crack as soon as you notice it. It will keep you from having to do bigger and more expensive repairs such as resurfacing or a complete driveway replacement.
Types of Driveway Sealers for Cracks
The best driveway crack sealer depends on the type of driveway, your budget, and how wide the crack is. Here are some of the different types of driveway crack sealers available in the market.
Expanding Polyurethane Foam
This is the most common type of crack repair sealant for concrete driveways. It’s cheap and easy to apply, though it doesn’t last as long as other types of sealants. The sealant comes in the form of a foam that expands once you inject it into the crack.
To make it last longer, use polyurethane foam along with a water-proof sealant or caulk. Inject the foam deep into the crack, then once it sets, cover it with caulk.
Here’s a video showing how to use expanding foam to repair concrete cracks.
Epoxy Sealant
If you want a longer lasting solution, use epoxy filler or sealant. It works best on concrete driveways. The main downside of epoxy sealant is that it requires the skills of a professional. It’s also more expensive, especially once you add the cost of hiring someone to come and seal the cracks.
You can see from the video below how involving the process is. That’s why it’s mostly used for structural crack repairs on foundations and walls.
Hydraulic Cement
Hydraulic cement is a type of cement that dries very quickly (within minutes). Because of its fast-drying nature, it’s often used to seal cracks on walls, foundations, driveways and other concrete surfaces.
To use hydraulic cement, you have to first mix it with water then apply it on the crack. You’ll need to apply it quickly since the mixture will harden if you take too long.
Concrete Filler Rope
Also called caulk saver foam, concrete filler rope is used to fix deep cracks on the driveway. But it’s not used on its own.
You first push the foam rope into the crack, then apply sealant/caulking on top. This allows you to fix deep cracks without using a lot of caulk (hence the name, ‘caulk saver’).
These filler ropes are sold in different thicknesses, so you can easily find the right size for the particular crack you want to repair.
Concrete Patch
A concrete patch is ideal for repairing small cracks on the driveway. Most concrete patches come premixed, so you can apply it immediately. Others come dry and you have to mix with water before application.
Most concrete patches are textured so that they match the feel of the rest of the concrete surface. This also ensures you don’t introduce any slippery areas on your driveway.
Patching can also be used to repair peeling and other kinds of surface damage on the concrete driveway.
Rubberized Asphalt Crack Filler
Most of the products above are suitable only for fixing concrete cracks. If you have an asphalt driveway, a rubberized emulsion crack filler is the best choice.
The main downside is that you cannot apply it yourself since it requires a hot pour. You’ll need to hire a pro with an asphalt crack repair machine that heats and pours the filler.
Cold Pour Asphalt Crack Filler
If you want to fix the cracks yourself, look for a cold pour asphalt crack filler. This doesn’t require any heating, so you can apply it yourself.
That said, cold pour asphalt crack filler has several disadvantages.
It requires a longer period to cure compared to hot pour filler, it’s not as pliable as hot filler meaning it doesn’t adjust to a change in temperature (this can cause future cracks in the asphalt), and it doesn’t bond as well as hot pour filler to the asphalt.
Cold pour crack filler is only a temporary solution. If you have the budget, you are better off hiring contractors to come and fill the cracks with proper rubberized crack filler.
Asphalt Patch
If you have wide and extensive cracks, consider using an asphalt patch. You’ll need to cut out the entire cracked section and then apply the patch.
You can also use an asphalt patch to repair potholes on the driveway.
Asphalt patches typically come in buckets. You pour the patch onto the area you want to repair (after doing the necessary prep work), spread it evenly, pour a bit of water on it to activate it, then tamp it down.
Some asphalt patches are also available in a thick liquid form. It’s great for repairing multiple small cracks in an area. You pour the liquid over the area then smooth it with a trowel.
Asphalt Sealant/Caulk
For minor cracks that have just started to form, a tube of asphalt crack sealant or caulk will do. These are also labeled as blacktop fillers.
How To Fix A Concrete Driveway Crack
The most important thing is to prep the area that you want to repair. Otherwise, the filler/sealant won’t work well. Use a wire brush to clean the crack then use a shop vac or leaf blower to get loose dirt and debris out of the crack.
Next, prepare your filler.
With simple caulk fillers, you simply cut the top of the tube and attach a caulk gun. Make sure you cut the tip at the point where it’ll be the same width as the crack. This ensures that the caulk gun lays a thick enough bead to fill the crack.
If you are using a 2-part epoxy filler, follow the instructions on how to mix it. Only mix the amount you need since you cannot store any remaining mixture. The same applies to hydraulic cement.
Once you apply the filler, use a putty knife or some other tool to smooth it over the crack. Some fillers require that you make a V shape ident at the top to increase its strength.
How To Fix A Crack On An Asphalt Driveway
As with a concrete driveway, the first step is to prepare the area. If you can’t get into the cracks using a brush, hose down or power wash the entire area to remove loose debris.
Let it dry then apply the crack sealer.
If you are dealing with one or two small cracks, use a tube of blacktop caulk. If the cracks are deep and wide, cold pour or hot pour asphalt crack filler is ideal.
If you have an extensive area filled with small cracks, use an asphalt patch to cover the entire section.
Make sure you check the directions regarding curing. Wait until the recommended period before driving or walking over the repaired area.
Can You Fill Driveway Cracks With Sand?
Looking for a cheap way to repair driveway cracks, some people fill them with sand, usually polymeric sand.
While not the best material, polymeric sand can be enough to fix small cracks on the driveway. Consider applying a crack sealant over the sand to further enhance it.
Can You Repair Concrete Driveway Cracks With Concrete?
It seems obvious, right? You have a crack on your concrete driveway. Why not just pour new concrete into it?
Unfortunately, this does not work. That’s because concrete doesn’t contain any bonding agents and thus will not attach to the old concrete.
As the new concrete cures, it will shrink and easily pull away from the old concrete, leaving the crack in place.
You should only use crack sealers or concrete repair mixes to repair cracks on a concrete driveway. These have special compounds that ensure the sealant adheres to the old concrete.
Final Thoughts
We recommend having a tube of crack sealer on hand to fix cracks as soon as they appear. This will save you the trouble and costs of fixing large cracks or other kinds of damage in the future.
Something else to consider is whether your driveway is too far gone to bother repairing it. If there are cracks from one end to the other, you are probably better resurfacing the driveway or replacing it altogether.
