How to Use Concrete Acid Stain – Part 1: Surface Preparation

Concrete acid stain is one way to ensure that your home has gorgeous flooring without having to spend a bundle on carpet or hardwood floors. Between its beautiful finish and easy maintenance, what’s not to love?

There’s more than one way to acid stain concrete. But for most concrete acid stain applications, the method in this article series will work just fine.

Preparing the surface for staining

This step is perhaps the most important in the entire acid staining process. Without proper preparation, your concrete acid stain won’t give you the rich color that you’re hoping for.

To accept the stain properly, the concrete must be completely free of oils, dirt, debris, sealers, or waterproofing agents. For older or exposed concrete, the surface must be completely intact, without any exposed aggregate. Concrete acid stain does not stain rocks or sand. It only works on the cement portion of concrete.

Cleaning the concrete

Remember: concrete acid stain is not an overcoat. It is a penetrating stain that will change the actual appearance of the concrete. If your concrete surface has any debris, such as tile adhesives, carpet adhesives, pet stains, dry wall mud, etc., you need to clean it thoroughly before staining.

Here are a few cleaning agents and the kind of debris they’ll clean up:

•   Bean-Ne-Doo: for removing adhesives and latex paint
•   Soy Gel Professional Paint Stripper: for removing epoxy, sealers, varnish or paint stains
•   Xylene: for removing solvent-based sealers
•   Soap and water or an orange degreaser: for removing water-based sealers or stubborn dirt

You can also use a fine sanding pad on a floor buffer to help open the pores of a distressed concrete and even the surface. This kind of surface will have more distinct color variations from the stain, which will give your floor depth and character.

Overlay resurfacing

It can be difficult to clean a concrete surface for staining, but it’s not impossible. If your concrete is too soiled for the above solutions to work, or if you’d prefer a more even finish, consider an overlay resurfacing.

Using an organic degreaser (such as DCI Orange or Simple Green) at a medium concentration, scrub the surface thoroughly with a nylon brush and rinse with clear water. For an interior project where water runoff is not possible, use a shop vacuum, mop, and/or a squeegee to contain the water and aid in drying. As a final step, rinse the surface with water and ammonia to fully neutralize it and ensure a balanced pH level for staining.

Final tips

Remember to remove all soap and cleaner residue from the concrete and make sure that the surface is completely dry before using concrete acid stain. Also, concrete that has been acid etched or washed with muriatic acid cannot be acid stained.

Filed under: Q & A by Shawna