Transform Your Sidewalk
The look of stone— without the extra labor or expense
Give plain old concrete the look of stone pavers.
This sidewalk was just your basic concrete—in pretty good shape but with zero curb appeal. To change that, I considered tile, stone and even complete replacement. Then I discovered “overlay,” a cementbased topping for existing concrete. It’s used mostly by pros, but I found a supplier who provided materials and rental tools and encouraged me to do it myself. I’m glad I did! With a helper, it’s a manageable process, and the total cost was about $800, less than one-fifth of the pro bid I got.
Prep your sidewalk
Old sidewalks are seldom perfect, but this one was in decent shape, without any cracks. If yours has cracks, you’ll need to properly repair them before applying an overlay. If you don’t, those cracks will promptly transfer to your new overlay. If your sidewalk has some heaves or uneven sections, you’ll need to grind them reasonably level before applying an overlay. In this case, I just needed to thoroughly clean the sidewalk. This included edging it to remove any overgrowth, sweeping off debris and pressurewashing with a degreasing detergent.
1 FILL THE JOINTS
Fill the control joints to create a flat surface for the gauge rake to follow (Photo 1). Otherwise you’ll end up with dips in the overlay. The concrete mix I had on hand filled the joints, but mortar mix would have been easier to work with. I marked the joint locations with garden tags so I could recut them later (see Photo 2 inset).
2 PRIME THE CONCRETE
For a strong bond, the overlay requires a special primer that must be covered with overlay within two hours. At first, my helper and I primed only a few feet of sidewalk. But after mixing and pouring our first bag of overlay, we realized we’d be able to move pretty quickly, so we primed the whole sidewalk.
3 ADD COLOR
We wanted to darken our overlay a little, so we added powdered pigment to the water and thoroughly mixed it before adding the overlay mix.
4 MIX THE OVERLAY
Thorough mixing is a must. Use a heavy-duty corded drill with a 1/2-in. chuck and a mixing paddle. If you don’t have a heavy-duty drill, get one. (I burned up a standard drill while mixing this stuff!) With the Brickform product, after initial mixing, allow it to set, or “slake,” for three to five minutes, and then mix again.
5 SPREAD THE OVERLAY
Pour the overlay onto the primed surface. This product required a thickness of 3/8 in., so I used a gauge rake in order to get a consistent depth. A gauge rake has an adjustable cam or foot on each end, allowing you to set the depth you need. Rake carefully, pulling and pushing the product for even coverage. Don’t let the cams slip off the edge of the sidewalk.
6 SMOOTH THE OVERLAY
After raking, smooth the overlay with a standard floor squeegee. At first I found the squeegee a little difficult to control because the edge wanted to dig into the overlay. But I got better with practice!
7 COAT THE STAMPS
Spray each stamp with a liquid release to keep the overlay from sticking to the stamp. We used a garden pump sprayer, which proved easier than a trigger-type spray bottle.
8 STAMP THE OVERLAY
Set each stamp down carefully, the whole stamp at once. Don’t slide them, drag them or set one corner down first. Walk on each stamp to ensure a full, deep texture. If necessary, use a tamping tool to force the stamp down. Don’t use a cast iron tamper, though. The hard edges can dent the texture. Instead, use a soft-faced tamper.
9 LIFT THE STAMPS
After a stamp is fully imprinted, set the next stamp and then lift the previous one. When you lift a stamp, lift straight upward so you don’t mess up the texture.
10 TOOL GROUT LINES
After lifting the stamps, you may have to tidy up some grout lines. A roller tool like the one shown works well for this; it creates the grout lines and adds texture to the edge of the stamped area.
11 TEXTURE VERTICAL SURFACES
We applied the overlay to the steps as well. The horizontal surfaces are done exactly like the sidewalk. For vertical surfaces, we applied a thinner overlay—about 1/4 in. thick—and then used a texture mat to stamp them. This flexible mat also proved indispensable for getting texture right up to the house.
12 GET UP CLOSE
We used stamps to get as close as possible to the house, but where we had to use the texture mat, we added the grout lines using a brick-jointing tool.
13 RECUT CONTROL JOINTS
Once the overlay has hardened, mark and recut the control joints. Caution: As we were stamping, a couple of our stamps didn’t come out perfectly square with the control joints. So, when we recut those, we cheated them a little bit to keep the cuts square with the pattern. One of those cracked at the original control joint within a week. So, as you’re applying the stamps, take care to keep the pattern square with the control joints.
14 APPLY STAIN
Mix the concentrated stain with water in a gallon jug, and then apply it using a hand sprayer. Apply generously, allowing the stain to pool in the low spots. Those pooled areas end up darker, giving a more natural stone look.
15 SEAL IT AND YOU’RE DONE!
When the stain is completely dry, use a paint roller to seal the overlay. Unlike applying the stain, don’t allow the sealer to puddle, because it won’t cure properly. We used a brush to fully coat the grout lines and also on the stoop to get up close to the house.