New LIfe for Ugly or Bland Concrete
By Lee Wallender, About.com
Is there anything less attractive than a monolithic slab of gray concrete? How about a scuffed, marred monolithic slab of gray concrete? In either case, you can give new life to your bland concrete slab with a technique called “stained concrete.”
Stained Concrete Is Not…Stained Concrete
Today, there is no excuse for that gray concrete slab. New techniques are coming down the road–and being improved–to make concrete look less like concrete. One method is stamped concrete. But stamped concrete only affects pattern and texture, not color. Stained concrete imbues your concrete with a huge variety of colors. Stained concrete is a misnomer. When I think of “stained,” I think of a coffee cup spilling on a white sofa. But concrete stain is actually a chemical reaction between the acid stain and the cement within the concrete mix. This bears emphasizing. Concrete is made of both aggregate (rocks) and the binding cement. Because concrete stain works through a chemical reaction between the stain and cement, the aggregate will not stain.
What is the Process of Concrete Staining?
Concrete staining is not the same as adding pigment to wet concrete. Concrete staining is done on cured concrete, and it can be done by the homeowner. First, you clean the surface. You’ll want to use an organic degreaser at medium strength. Note that because concrete stain is a chemical reaction, surfaces previously treated with muriatic acid or otherwise acid-etched cannot be stained. Imperfections in the concrete (that is, the other kind of “stains”) will show through. Concrete stain is not a cover-all. Also, you may need to lightly sand down the concrete to open up the surface. Concrete stain can be applied in many ways (mops, brushes, rollers), but experts such as Direct Color, Inc. recommend spraying on with an ordinary sprayer such as you might use for herbicides. This provides for a wider, smoother broadcast of the concrete stain. The concrete stain can be diluted with water, which allows for a lighter application of stain. But if too much water is added, the chemical reaction with the cement will not take place. What you see at first is not the end color. It takes up to 8 hours for the chemical reaction to take place. Don’t walk on the concrete stain because your footprints may end up permanently on your concrete.
Concrete Stain Kits
Concrete stain kits are available at your local hardware store. These kits contain everything you need: the stain, sealer, gloves, instructions. Keep in mind, though, that they may not cover a lot of square footage: perhaps as little as 200-400 square feet. However, a concrete stain kit may be a good way to experiment with a little-used section of patio or even the concrete pad underneath your AC unit–before moving to the bigger areas such as driveway.
A Trend That’s Catching Fire
By Lee Wallender, About.com
Excuse my excitement, but stamped concrete is awesome. Stamped concrete is one of those home remodeling trends that seems to be catching fire lately, and for good reason. I’ve seen stamped concrete for years, and wasn’t much impressed by it. Only expensive commercial applications looked decent, and even that was a stretch. Recently, though, new texturizing and pigmenting trends allow homeowners to introduce stamped concrete to their exteriors.
What is Stamped Concrete?
Stamped concrete involves pouring slab concrete for driveways, walkways, patios, etc., and then impressing both patterns and textures onto the concrete before it is fully dry. For many years, a lesser form of stamped concrete was often seen that merely duplicated patterns. But the newer types of stamped concrete impart textures that duplicate many different surfaces such as cobblestones, brick, pavers, wood, seashells, and more. Also, pigment is usually added to stamped concrete to further duplicate the look of such patterns.
Why Stamped Concrete Instead of the Original Surfaces?
Brick, pavers, and cobbles look great, but since they form a surface of many interlocking pieces, they are susceptible to frost-heave and other changes in the underlying surface. Sometimes this can be good, if you’re trying to cover an uneven surface–the brick, pavers, stone, or pavers will conform to the surface. But if you have a good, flat, and level undersurface, you’ll want your concrete to be laid the same way. Reinforcing rods within the stamped concrete help to tie the pavement together and strengthen it. Also, bricks, pavers, cobbles, etc. allow for weed to grow up through the cracks. Since stamped concrete is a solid, continuous surface, nothing can grow up through the “cracks.” As you may already know, the “cracks” in stamped concrete are simply impressions in the concrete that only partially go through the surface.
Does Stamped Concrete Look as Good as Brick, Pavers, Cobbles, etc?
It’s all in the eye of the beholder, but in my view it does not. Aesthetically, it’s a close second. I have seen stamped concrete that attempts to duplicate the look of exterior wood plank flooring. It looks great on its own terms, but it can never be mistaken for the real thing. As such, you may want to choose stamped concrete that isn’t trying so hard to duplicate something else. Stamped concrete can have any number of patterns, textures, and colors.
Can I “Do it Yourself” Stamped Concrete?
Not recommended. The process of laying stamped concrete is almost an art. Not only that but special tools and an experienced crew of up to four people are needed. Save yourself the frustration and find a good concrete contractor who has experience in laying stamped concrete.
What’s the Process of Laying Stamped Concrete?
In brief, stamped concrete is laid like this:
- Place the concrete. Concrete should be no less than four inches thick.
- Add color. Color is added either in the mixer or after concrete placement. The first method is called “integral coloring” and the second method is called “broadcast or surface coloring.” Broadcast coloring involves evenly spreading dry color across the surface of the concrete.
- Apply release agent. Release agent allows the texturizing mats to come off without taking off concrete.
- Lay mats. Texturizing mats are laid in succession. Since there are usually not enough mats to cover the entire surface, when one is finished it is applied to another area of the concrete.
- Let dry 24 hours.
- Pressure wash the release agent off.