How to Acid Stain a Concrete Floor

I love stained concrete floors. It gives a room that cool modern industrial vibe and the best part is that it’s way more affordable than other flooring options.

To me, doing acid stained concrete floors in a basement just makes sense. The concrete is already there, so it doesn’t take a ton of work to create a nice looking floor. Also, basements are an area of the house that are at most risk of flooding. With concrete floors, you don’t have to worry about any potential water damage to your flooring.

In the farmhouse, we did acid stained concrete flooring in the basement and we were very happy with the way it turned out. So naturally, we decided to do it in the basement of the new house as well.

It’s a very straight forward process, and in this tutorial, I’m going to teach you just how I did it.

Step 1: Clean the Concrete

When acid staining concrete floors, it’s extremely important to clean the concrete very well before doing anything else.

I started by scraping any dried drywall mud and paint off the floor. Then I used a vacuum to remove all of the dust, dirt, and debris.

Then in a bucket, I mixed some soap and water and mopped the entire floor. Then mopped it two more times with clean water.

Step 2: Etch the Concrete

The second step in the process is also very important. I applied a special etching solution to the concrete. So what exactly does this do? It basically opens the pores of the concrete to allow the stain to get down into the surface.

I mixed the etching solution with 4 parts water in a mop bucket and applied it to one 10 x 10 ft section at a time.

Then I scrubbed that area with a bush and let stand for about 5 minutes.

Since the etching solution will leave a chalky residue if you let it dry, I rinsed and cleaned each section before moving on to the next.

I repeated this until the entire concrete floor was done.

Step 3: Apply the Acid Stain

After I had cleaned and etched all of the concrete, it was time to apply the stain. For this, I used two garden sprayers. Any kind will do. I filled one up with clean water, and in the other one with the acid stain.

I chose the color Graphite, which is a warm gray. I really like the subtle color that it adds to the concrete while still keeping a natural look.

Again, I worked in 10 x 10 ft sections. Using the sprayer filled with plain water, I dampened the section I was working on. The key here is to only dampen the surface without leaving any standing puddles. This will help prevent acid burn.

Then using the sprayer filled with the stain, I sprayed it on in a back and forth motion until that section was covered. I repeated this process across the entire floor.

Step 4: Clean and Neutralize

I let the stain do its thing for 24 hours. When I came back, I mixed 1 part degreaser neutralizer with 4 parts water in a mop bucket and used it to clean the entire floor.

This removed all of the acid residues while also neutralizing the acid. After I mopped the entire floor with the neutralizer, I went over it a few more times with clean water.

Step 5: Seal the Floor

After cleaning the floor one last time, I let it dry for another 24 hours. Once it was nice and dry, I applied sealer to the concrete.

I opted not to use a solvent-based sealer because of the harsh order. And I like the satin finish that the acrylic sealers produce.

I poured the sealer into a paint pan and applied it using a regular paint roller on a pole. In total, I applied three thin coats, letting each coat dry thoroughly before applying another.

Step 5: Enjoy Your Stained Concrete Floors

Here’s a shot of the finished stained concrete floors! In this photo, you can see our basement rec room and home gym, along with the double barn doors I built.

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