Staining concrete floors indoors

Staining concrete floors indoors

Do you have some concrete floors at home and you’re looking for options on how to decorate them and have come upon concrete staining? Maybe you have seen some concrete floor finishes that turned out to be staining and want some for your own house?

These are both good reasons to look for more information and I’ve tried to write in detail about this subject so you can know more about it as well. If you want to have concrete floor stain in your home, it’s even something you can achieve yourself if you know your way with some tools.

Stained concrete floors in house

Concrete stain sounds like something that would be very difficult to get out of the rug. You know the story: the construction worker in the family comes home with boots covered in gray, and soon it’s all mashed into the carpet.

Well, it’s time for a radical re-orientation on the topic of concrete stain. Instead of a messy problem, it’s actually a way to decorate. And not with concrete, but acid. The design possibilities are endless and very attractive.

For those who don’t want to work with acids, you can use water-based concrete stain or film-forming stain. Both are valid options, but they work a bit differently from acid stain.

How concrete staining works

Staining concrete isn’t actually always done by acid. Instead, it sounds much more like a recipe: salt and lime (metallic and hydrated, respectively) react with the concrete to make wonderful colors and surprisingly intricate designs.

Another great thing about these stains, aside from the patterns and colors, is the overall look. Concrete, once it’s been stained, doesn’t look like it’s been colored. Instead, the sheen created looks very natural, as if the concrete had always looked that way.

When you compare acid stains and the two others mentioned before, the difference is in the working method. Acid stain works with a chemical reaction while penetrating stains fill the pores of the concrete. Film-forming stains resemble more floor sealers.

For this guide, we’ll be concentrating on the acid stain as it might be the most challenging one. It’s also the most common one so I’m using it for that purpose as well.

Painting or staining concrete floors depends on what you wish from the end result

How to apply concrete stain indoors

Using an acid stain to treat an indoor concrete floor can produce a variegated marbling or mottled pattern in various earth tones. Unlike a non-reactive water-based stain that only coats the surface, a reactive, acid-based concrete stain penetrates between 1/16 to 1/32 inch of the concrete to create a permanent new look to your floor.

If you have floors in bad condition, look some of our how to fix concrete cracks guides to see if there is a good solution there.

Begin with cleaning the floor

Indoor concrete floors that are treated with an acid stain must first be cleaned and prepared before the stain is applied. In order to get the best results, any old glue, paint, waxes, grease, or paint must be cleaned from the concrete.

These contaminants can appear on the surface and be quite visible or they can seep into the microscopic cracks of the concrete. A good scrub with a trisodium phosphate and water mixture or other phosphate-free concrete cleaning product will help make sure your floor is ready for staining.

After applying the cleaning agent, allow it a chance to work, and then use a mop and some freshwater to remove the excess residue. If your floor has any cracks or other imperfections, take the time to patch and repair them.

Never use an aggressive acid wash when trying to clean a concrete surface before applying an acid stain. The harsh nature of such a product will destroy the natural beauty of the aggregate used in the concrete making process and yield inferior results when you attempt to apply the acid-based stain. Once the floor has completely dried, you are ready to apply the stain.

Things to consider before staining

When staining concrete floors indoors, you have the choice of leaving the floor in its original condition or adding some interest and detail by scoring and perhaps adding some stencil work to your interior floor. If you intend to give some depth and add a pattern to the concrete, do so before you apply the stain.

To create a 3-dimensional look, you can use an angle grinder to make scores of approximately 1/16 of an inch in depth. Use a straight edge to get uniform and consistent lines. Once the scoring and possible stenciling has been completed, make sure any concrete dust and other excess are cleaned and the surface is clean.

You may choose to use the acid stain at full strength or you may want to dilute it with water. By adding water, the stain will have a more subdued effect on the changed appearance of your interior concrete floor. Use caution when you begin to apply the stain as you are, after all, working with an acid-based product.

Applying the acid stain

The stain can be applied by using an inexpensive garden-type plastic pump sprayer. It can also be applied with a soft bristle brush. No matter which way you choose to apply the stain, use a thin coat that will saturate the surface but will not be so thick that it will cause puddles to gather in certain spots.

Be careful if using a brush not to press too hard or you can create an annoying pattern of visible brush strokes right into the concrete surface. Once the stain has dried, a residue will form and it will need to be neutralized with a water and ammonia mixture. After applying the mixture, rinse the surface again with clear, freshwater.

Your newly stained floor should have a beautiful and permanent new look with a distinct range of darker and lighter color patterns. The colors are earthy and vary in terms of intensity based on the degree of limestone and other organic materials that underwent the chemical reaction. To maintain, you may apply wax once or twice per year and then periodically mop down with water and a mild detergent.


You should have a picture now about how staining concrete floors indoors works. The process is simple, but might take some work and practice to do perfectly.

When it comes to any kind of floor decoration, it’s important to fix the imperfections on the floor, and if the patches show, you might need to try to fade them with the stain.

The problem with the old floors is that most of the time they do need fixing. If the patches can’t be faded as you want, it might be worth it to consider resurfacing and staining that.

It might not be an option many people want to hear, but personally, I’d take the extra steps to have the best floor that I can. Some wizards can fade most of the fixes, but I do decorative work so randomly that I rather make the conditions perfect before I start.

Leave a Comment

Your email address will not be published. Required fields are marked *