When working with concrete stains and chemical etching solutions, proper safety precautions should be taken. Wear protective gear like eye protection, gloves, a respirator and long pants.
For acid-based staining, use a hand-held pump sprayer that’s compatible with the product specifications and mix the stain and etch solution according to the instructions.
Basic Staining
Concrete isn’t just for basements, garages and sidewalks anymore – it’s the new pallet for the modern home and garden. It can be molded into different forms; brushed or swirled; tinted and painted in artistic patterns. Staining concrete is one of the most cost-effective and durable ways to alter its look.
When working with paints, stains, dyes and sealants, safety should always be the primary concern. A respirator mask and protective goggles are a must for anyone working with chemicals. Depending on the situation, a long-sleeved shirt and pants may also be wise. The workspace should be well-ventilated, and fans should be used to improve airflow.
The surface of the concrete must be clean, free of oil, dust, dirt and other contaminants. It is best to use a power grinder for this task, but chemical cleaners are also available to meet the needs of specific surfaces and contaminants. It is very important to prepare the surface of the concrete to accept the stain, and this can be accomplished by using a mechanical grinding method or by chemical preparation.
A water-based stain is often the first choice for beginners because it is easy to work with and produces consistent results. The stain can be rolled or sponged on, but a nap roller will usually yield the best and most even results. If more coverage is desired, an opaque stain can be used instead of a translucent stain. It is a good idea to test the color of the stain on an inconspicuous part of the surface prior to application, and the manufacturer’s instructions should be followed for proper application.
Acid staining is a more difficult technique, but it can be quite effective. The basic process involves a combination of water, muriatic acid and inorganic metallic salts, which react to change the concrete’s natural gray color. The acid etches the surface of the concrete to a small degree, and helps the stain penetrate more deeply. The etching process must be completed and the concrete allowed to dry for the recommended amount of time before staining.
Misting
Before any staining can be done, the concrete needs to be thoroughly cleaned. This can be achieved with a stiff broom, pressure washer or mop. After rinsing, the area should be vacuumed to remove any lingering dust or debris that may have settled. This is particularly important if the concrete has been previously coated with old sealers, paints or adhesives that need to be removed before staining can begin. It is also imperative that proper safety precautions are taken when working with chemicals such as staining agents. Always work in a well-ventilated area and use fans to circulate air and reduce the likelihood of inhaling fumes. This is especially important when working with acid stains, which can cause serious respiratory issues if inhaled. Use a respirator mask, goggles and gloves to protect yourself.
Once the surface has been properly prepared, misting can be used to help maintain moisture levels and keep the concrete slab from drying out during the curing process. The expert who performs this step will spray a fine mist of water across the surface of the concrete slab regularly, usually on a daily basis. This technique is sometimes referred to as “wetting.”
Another option is to cover the concrete slab with a plastic sheet, which will also help prevent the surface from drying out. This method is a bit more time consuming than simply spraying the concrete with a mist, and it requires bricks or other heavy items to hold the sheet in place. However, this is a great way to keep the concrete from drying out during the crucial first few days of curing.
In addition to using misting and covering techniques, the experts who specialize in stained concrete installation will often employ additional special effects to create unique results. For instance, they may etch the concrete prior to staining, or even apply an etch solution afterward to further open up the pores of the concrete for better absorption of the color. They may also sprinkle kitty litter or rock salt onto wet stains to attract the stain to them, or scatter aluminum shavings on acid stains to create a chemical reaction.
Special Effects
The plain gray, brown, or almost white surface of concrete can be made to look more decorative and cover blemishes with a variety of staining techniques. Stains can be used to create a wide range of effects and mimic everything from polished marble to tanned leather. The possibilities are only limited by your imagination and the type of stain you choose.
There is a lot of information available online on how to stain your own concrete surfaces, but we highly recommend that you leave the process to a professional contractor. Staining is a process that requires a thorough understanding of the material and a knowledge of proper prepping methods that most DIYers are not going to have. Stains available for do-it-yourself use are also not as robust or permanent as the professional-grade stains used by contractors.
Wet-on-wet layering is one technique that can be used to create a unique color pattern in your stained concrete. By applying a second coat of stain while the first is still wet, you can create a gradient effect or even blend several different colors together. Veining is another popular way to create a unique stain pattern in your concrete. By spraying a second color of stain onto the initial stain while it is wet, you can create a marbleized effect.
Stenciling is another popular way to add a graphic design to your stained concrete surface. Stencils can be purchased or made at most home improvement stores and are easy to work with. By carefully securing the stencil to the concrete and spraying the desired color of stain through it, you can create a beautiful patterned effect on your stained concrete.
Scoring, engraving, etching, and stenciling are all great ways to add texture to your stained concrete. These processes will alter the surface of your concrete slab, making it more appealing and increasing its slip resistance.
Before starting any of these techniques, we recommend doing a small test area with the next stain color to make sure you are happy with the results. Some acid stain colors do not show much characteristic color in liquid form and may lighten or darken over time as the concrete oxidizes.
Sealing
Applying a sealer is the final step in the staining process and it is arguably the most important. It not only provides a beautiful glossy finish to the concrete but it also protects the surface from dirt, oil and chemicals. Sealers can be applied by hand or using a sprayer. Before sealing the concrete it is important to ensure that the stain has completely dried. This will normally take 24 hours.
A few things to keep in mind when applying a sealer are that it is best to work outdoors or inside a covered area and to use a mask, safety glasses, gloves and long-sleeved shirt. Working with paints, stains, sealers, adhesives and other chemical products can be hazardous to your health. It is also highly recommended to open windows and doors in the workspace to improve air flow.
During the etching stage, it is important to note that the acid solution will remove some of the concrete surface which can be problematic for those wanting to reseal their concrete in the future. It is also important to thoroughly clean the concrete once the etching has finished. This will help to prevent any problems such as oil or grease from causing the stain to flake off.
Before starting to apply the sealer it is best to tape off any areas that you do not want stained. It is very easy for decorative stains to drip where they are not supposed to and it can be almost impossible to remove the stain if this happens. It is also highly recommended to lay a water-resistant cover material over the masking tape for added protection. For cleaner-looking edges or more intricate styles, laying duct tape over the masking tape is also an option.
It is highly recommended that you read the manufacturer’s recommendations and follow their guidelines when applying a sealer. They will usually recommend the amount of product needed to be applied, although this will vary depending on the type of sealer you are using and the condition of the concrete. For the best results, it is a good idea to apply several thin coats of sealer rather than one thick coating.