Concrete Stain: Using Acid Stain vs. Acrylic Stain

Using concrete stain is an easy and inexpensive way to spruce up that boring gray concrete and bring some color and life to your patio, porch, basement floor, etc. Instead of paint, you want something that's not going to chip or flake and let your concrete maintain some of its natural appearance. You've probably heard of acid stain and maybe even seen some examples of how these stains can transform the look of a concrete surface. There are also acrylic stains designed for concrete which may be more suitable for your situation and taste.

The first step in a staining project is determining which type of stain to use, acid or acrylic. You must consider the condition of the concrete surface and how you want it to look when finished.

Acid staining is a natural coloring process in which the stain reacts with free lime to produce translucent colors. Every slab is different and there are many variations throughout each slab itself. This is why acid stains create a mottled or variegated appearance. Any inconsistencies, imperfections, or defects in the surface will be highlighted or become more noticeable with acid stains. An easy way to test this is to wet the surface. Any variations that become apparent with water will do the same with acid staining. Most previous stains such as grease and oils will stand out. Scratches, chips, divots, and cracks will stain darker becoming much more noticeable. No concrete slab is perfect so don't let minor imperfections discourage you. Color variation is heart and soul of acid staining and is what makes it so appealing.

As stated earlier, acid stains will highlight inconsistencies. This includes any patchwork or filled cracks. Some minor patching here and there won't be a big deal, but major patchwork such as divots caused by removing carpet strips will be very obvious. Acrylic stains will be a better option, or perhaps an overlay prior to concrete stain.

As concrete ages, especially exterior concrete, leaching takes away the free lime needed for acid staining. So older concrete may not be a good candidate. You're not going to get the desired results. Exterior concrete that's over 10 years old is probably a better candidate for acrylic stains.

An acrylic concrete stain is semi-translucent and creates a more uniform color. It doesn't react with concrete, but penetrates the pores and adheres to the concrete, acting like a dye. You have much more control over the outcome and acrylic stains will help mask some the surface defects and variations. They are much easier and safer to work with which is a major plus for the average do-it-yourselfer. Also, acrylic stains are available in more vibrant colors. If you're wanting a brightly colored surface, then choose acrylic stain.

Perhaps the best part about acrylic stains they don't need to be neutralized or rinsed. Although I'm a big fan of acid staining, the process of neutralizing and cleaning up residue can be a long and painful task on big interior floors. With acrylics, I can just sit back, wait for it to dry, and start putting down the sealcoat.

You're not absolutely stuck with choosing one type of stain. You can utilize both acid and acrylic stains using faux finishing tachniques. Faux finishing can also fix a bad acid stain job, as long as it's done before the sealer goes down.

Don't rush into a concrete stain project without considering the options. This is a nonreversible process and fixing a poorly stained slab can be a vigorous task.