While reactive stains offer all kinds of design possibilities, they are a tricky subject for a collection of recipes. The central claim of a recipe is that if you use the specified products and follow the directions to the letter, the result will be something, if not identical, then at least very similar to the original. Well, reactive stains will have none of that. Gaye Goodman, owner of New Mexico-based Faux Real Floors LLC and one of our contributors for this section, points out that acid staining simply can't be done by following a formula.
Bart Sacco, of Concrete Texturing Tools and Supply, a Pennsylvania store, agrees. There is a huge list of factors - mix design, finishing method, dilution ratio, application technique - that affect how the stains react and what colors you'll end up with, Sacco says.
This anecdote from Goodman is a perfect illustration: "If it turns out that the builder's slab has a plasticizer added to the mix, and he wants a medium-walnut floor," she says, "we might have to dilute the stain 12 times over with acid water to keep it from going black!"
Taking all of this into consideration, our goal with these recipes is not to encourage you to reproduce specific acid-stained floors - which would be impossible - but rather to illustrate effects that utilize acid stain as well as other materials. These techniques will be applicable from one slab to the next.
Simon Motamed, Triple-S Chemical Products Inc. - Los Angeles, Calif. www.concrete-stains.com
Just one color of acid stain delivers bold, dynamic patterns thanks to the use of a secret ingredient: trash bags!
- Triple-S Chemical Products AL-70 lacquer, gloss
- Jet Coatings Elasticrete Magnesite Cement microtopping (EMC-60): White
- Triple-S Concrete Acid Stain: Tan
- Ammonia solution, 1 cup ammonia to 1 gallon of water
- Triple-S UT-70/30 One-Part Polyurethane sealer, diluted 9:1 with acetone
- Triple-S UT-9500 Two-Part Polyurethane, diluted 3:1 with acetone
- Special equipment required: Plastic garbage bags
- Over a thoroughly clean and dry substrate, apply a single coat of the AL-70 sealer and let dry completely.
- Put down two layers of white microtopping and let set completely.
- Apply one coat of acid stain and let dry completely.
- Tear the garbage bags open at the seams, so you have flat sheets of plastic.
- Clean any residue off the surface and apply a second coat of acid stain. While this coat is still wet, lay the plastic bags over the wet floor haphazardly. Scrunch and wrinkle the bags as much as you like, as the creases will collect the stain and give the finished floor the random patterns we're after with this technique.
- About 2 hours later, when the stain is partially dried, removed the garbage bags, then let the stain dry completely.
- Neutralize the floor by scrubbing it down with your ammonia solution, rinse thoroughly and let dry.
- Apply one coat of the one-part polyurethane sealer and let dry.
- Apply one coat of the two-part polyurethane and let dry.
- Apply a second coat of the one-part polyurethane and let dry.
- Finish the floor with a final coat of undiluted two-part polyurethane and let dry completely.
The Look of Cork
Gaye Goodman, Faux Real LLC - Albuquerque, N.M.
Creating a look reminiscent of cork or aged hardwood floors, this technique requires plastic sheeting and some well-coordinated teamwork.
- Bix Trisodium Phosphate (TSP) Substitute Concentrate
- Quikrete Concrete Bonding Adhesive
- Lyons Manufacturing Super Flowcrete self-leveling cementitious filler
- L.M. Scofield Lithochrome Chemstain Classic: Dark Walnut, Weathered Bronze (or possibly, Fern Green and Antique Amber)
- Acid solution, 10:1 water to muriatic acid
- Ammonia solution, 1 cup ammonia to 5 gallons water
- Envirosafe Trojan Masonry Sealer
- Harvard Chemical Sheen C-40 water-based acrylic sealer
- Special equipment: paint filter (or nylon stocking) in a large plastic funnel, a roll of 0.31 mil (very thin) painter's dropcloth plastic sheeting
- This application is designed for a brand new, smoothly troweled (not burnished) slab. If you're working with a preexisting slab or a slab with a different finish, your results will vary.
- Mask walls of room up to at least 24 inches from slab, and do the usual slab preparation. Remove paint and glue spots, scrub with TSP substitute and repair any holes or cracks using a coat of Bonding Adhesive followed by the Super Flowcrete. Before you start, make sure floors are clean and dry with no dusty concrete residue.
- Prepare plastic in advance: Unroll and unfold plastic to 6 feet longer than the room and 6 feet wider. Allow 3 feet for overlaps if multiple pieces need to be used to cover the floor wall-to-wall. With one person on each end of a large piece to maintain tension, roll it up loosely and lay roll on the floor parallel to the wall where you will begin staining. The loose edge of the plastic should be on the bottom of the roll, pointing towards the wall.
- Using the funnel with the filter, fill a sprayer with one part Dark Walnut diluted with two parts acid solution, or whatever dilution you have determined will create a light "paper-bag brown" color on the slab you're working on. Typically, one gallon of this mixture should cover around 200 square feet.
- Test the spray volume outdoors or in a bucket. You need a medium-mist round spray pattern that can be applied in circular motions to put down a very wet but even coat of stain.
- If you discovered, during testing, that your concrete reacts to the Weathered Bronze stain with green and brown tonalities, then fill a second sprayer with undiluted Weathered Bronze. If it does not, then mix equal parts Fern Green and Antique Amber in the sprayer. You'll need roughly a quarter gallon for every 200 square feet.
- Starting in the far corner of a room, Worker A applies the Walnut mix to approximately 80 percent of a 3-foot by 4-foot area. Worker B sprays the Weathered Bronze (or the Fern Green substitute) over 20 percent of the same area. The two sprays should overlap about 3 inches where they meet. Spraying is done quickly and heavily, so the floor is almost as wet as if the stain had been poured. Spray patterns should be in random puddle shapes with varying proportions to look natural: no straight lines.
- Worker C unrolls enough plastic to cover the wet stain and then kneels on it, making sure the plastic covers up to the edge of the floor. Then, Worker C stands facing the stainers, holding the plastic roll up and out of the way as they continue staining an adjoining area of about 20 square feet. As soon as the slab is soaked with stain, Worker C drops to his knees and pats plastic into place over the newly soaked section.
- Do not stretch or twist the plastic in any way. Let it fall loosely as it may. Worker C can walk on plastic-covered floor following behind the sprayers without fear of leaving footprints. Gas will lift large sections of plastic into bubbles. Do not try to eliminate them, as they will contribute to the design.
- Establish a rhythm, working quickly to stain and cover the entire floor. It helps to cut smaller sections of plastic in advance for indented areas like closets and around toilets. Carry a knife to split the plastic where necessary to go around protruding elements.
- Leave plastic down for the entire cure time of the stain (four hours). Note: This technique cannot be used on an absorbent slab, and it can't be done outdoors in windy conditions, as the plastic must stay in same position for the entire time in order to get the desired results.
- After four hours (or overnight, as convenient) lift away and discard plastic, even if large sections of floor are still gooey with stain, and then proceed with post-stain scrub using a white pad on the power buffer to remove all chemical residues. Vacuum with a wet-vac and rinse with a microfiber mop and the ammonia solution.
- If the patterns left by the plastic seem too stark, the floor can be lightly misted with the same colors or with one preferred color in a second staining. This step needs only 30 to 40 minutes of cure time before scrubbing. The plastic patterns will recede into the background under the second stain.
- Seal using one coat of Trojan Masonry Sealer as a primer and let dry. Then mop on three coats of Sheen C-40.
Jeroen H.F. Kaijser Bots
EuroFloors - Huntersville, N.C. www.eurofloors.us
Using iron shavings to alter the reaction of the stains, this recipe is ideal if you're after dramatic patterns and bold swirls of color.
- Savogran TSP Substitute
- Renaissance Concrete Chemical Stains: Ebony Stone and Vermont Slate
- Iron shavings (you can buy standard metal shot for shotblasting at a local machine shop or go to your local garage and ask for metal shavings)
- Ammonia solution, 5:1 water to ammonia
- For residential installations:
- Kemiko Stone Tone Sealer II water-based acrylic sealer
- ZEP Z-Tread UHS Floor Finish topcoat
- For commercial installations:
- Kemiko Sta-Crete 1600 water-extended epoxy coating
- SureCrete Dura-Kote Polyurethane Concrete Sealer
- Special equipment required: Floor buffing machine with a range of buffing pads
- Broom the entire area clean.
- Clean the slab with TSP solution and a blue or black pad on your floor buffer. (The type of pad you use will depend on the porosity of the concrete. Don't use an overly aggressive pad, as it can damage the concrete and expose the aggregate.) Do not use muriatic acid to clean the slab.
- Draft the design on the floor with white chalk. (Don't use colored chalk, as it will interact with the stains.)
- Spread the iron shavings in the outline of your design. The iron is going to react with your stains, rusting very quickly and lending great color variations to the final floor. As you spread the shavings onto your design, don't try to cover your shapes evenly. The more uneven you are, the wilder your final design will be.
- Mix the acid color for the design (for this application, the Vermont Slate), and your background color (Ebony Stone) in two separate pump sprayers at the ratios you've determined you want during preapplication testing.
- Spray the Vermont Slate onto your metal shavings.
- Immediately after, spray the background color around the design. You want the wet acids to flow into each other for additional effects.
- Once the acid has cured entirely, you're ready to clean and neutralize. First, sweep the metal shavings or shot off your surface. Then, using your floor buffer with a white buffing pad, scrub the floor with your ammonia solution. Wet-vac to remove the residue. Rinse the floor with clean water.
- If you're unhappy with your colors (the acids don't always take the first time), you can spray another application of acid to achieve the desired result. Repeat the cleaning and neutralizing process once your second application has had time to cure.
- Seal your floor. For residential installations, install two coats of the Stone Tone sealer, followed by three coats of Floor Finish topcoat. For a more durable finish, ideal for commercial jobs, use one coat of Sta-Crete with one coat of Dura-Kote to finish it off.
Tom Ralston, Tom Ralston Concrete - Santa Cruz, Calif.
A super-simple application technique that achieves a classic old-world finish, inspired by the multihued patina found in the palaces and cathedrals of Europe.
- L.M. Scofield Lithochrome Chemstain Classic acid stains: Weathered Bronze, Padre Brown
- Ammonia solution: 2 ounces ammonia in 4 gallons of water
- SuperStone Concrete Sealer
- Power-wash your surface thoroughly. The surface pictured above was hard-troweled, but this effect works just as well over a textured surface.
- Wet your surface down with a mist of water. This accomplishes two things: It will cool down your surface on a hot day (which will keep your stains from evaporating) and it will also help your stains run and bleed, getting the natural look we're after.
- Once you've misted lightly (you don't want a lot of standing water on the surface), put down coats of Weathered Bronze and Padre Brown stains simultaneously across the whole surface, even the vertical faces of steps. Keep in mind, as you work across the surface, not to let the edges of the stained area dry out before you've finished the coats - if they do, and you try to continue to stain from that dry edge, the color won't blend evenly and will turn out blotchy.
- You want to saturate the surface pretty thoroughly. As the stain settles, gravity will pull it towards the drains in a patio or down the faces of a staircase, leaving natural swirls and rivulets of color.
- Once your base coats have sat for 12 hours, wash and neutralize with the ammonia solution and check for areas that have not been stained. After the wash has dried, spray another coat of stain as needed in areas that did not color, which may include the faces of the stairs. This second coat needs to be put on with a light hand so your colors don't end up oversaturated (unless, of course, oversaturated is what your client is going for).
- Let your second coat dry for another 12 hours.
- Wash the surface vigorously with a hose and jet nozzle.
- Using the ammonia solution, scrub the surface clean, neutralizing the second application of stains.
- Let dry for 12 to 24 hours. Make sure it's completely dry or your sealer will fail.
- Seal with the SuperStone sealer, which will give it a bit of a sheen and really make your colors pop.
|Three Acid Stain Application Tips
Make sure you communicate clearly with your clients about the variability inherent in acid staining. Simply duplicating a floor is not doable, but Gaye Goodman sees that as an asset, not something to apologize for. "Most professional stainers consider the wide variability of results to be an advantage because it means that no two clients' floors will be alike. Similar, perhaps, but never alike."
When applying acid stains, always use all-plastic spray bottles, so your stains don't start reacting to things before they've even hit the floor.
Test, test, test! Find an out-of-the-way corner on your slab and run dilution tests to see what concentration of stain is going to yield the colors you're after. Jeroen H.F. Kaijser Bots, owner of North Carolina-based EuroFloors, says he tries samples with 25, 50, 75 and 100 percent stain solutions. And don't forget to test the sealer you plan to use as well, he says, since the sealer will affect how the colors look in the finished floor.