Concrete staining is much more than a solid color — curves, arches, radii, faux tile, faux marble, integral saw cuts, cracks, grout lines and other artwork and features can be incorporated into a final design. The potential color, texture and design are limited only by the imagination of the artist and applicator.
Previously the province of showrooms and ritzy commercial buildings, stained concrete's reputation as a durable, inexpensive and clean finish is growing. Concrete stains are now available in home centers and some paint stores and, of course, can be applied professionally by specialty contractors.
This finishing technique also is known as "acid staining" and "acid etching." But acid is not what actually strains concrete. Acid is the facilitator, opening up the top of the concrete, allowing metallic salts to react with hydrated lime (calcium hydroxide) in the cured concrete, creating the permanent coloring. Acid may be incorporated directly in the mix, or it may require a separate muriatic acid wash prior to staining (depending on manufacturer).
Concrete dyes subsequently may be used to enhance color and boldness within the stain design itself. Dyes penetrate the surface, rather than reacting chemically. Obviously, cleaning the concrete to remove grease, oil, mildew, drywall mud, caulking, glue and soap residue is needed prior to dye, acid or acid/stain application. Using a commercial patio cleaner and rinsing with a pressure washer is the typical recommendation.
Hard-troweled concrete is the ideal finish for staining. The concrete becomes burnished with each pass of the trowel, creating almost imperceptible high and low areas. Differing trowel-stroke angles and variable amounts of carbon contact from the metal trowel result in differing stain infiltration rates. The results can be breathtaking, with an uncanny replication of the mottling of natural marble. (Broom finish and aggregate generally are regarded as less desirable raw products, aesthetically.)
The concrete mixture can affect the finished product. It is important that the cement content in adjoining areas is similar, for uniform results. For example, adjoining patched areas likely will "flash" and may need to be skim-coated for best results. Air-entrained concrete has little effect on the finished stain, while calcium chloride concrete ad-mixtures typically produce unattractive blotchiness. Testing a small area is always advised.
Sealers are good for a particular matte finish and protecting against moisture. Three basic types of sealers are used on interior concrete slabs: acrylic, urethane and epoxy. Acrylics are easiest to work with and less expensive, but do not hold up as well due to a softer finished surface. Urethanes produce a good surface but do not fare well with higher moisture levels. Epoxy gives the hardest surface and seals best. Some sealers may have stains in the epoxy — obviously, anything other than clear would be detrimental to stained or dyed concrete. Wax or other floor finish is routinely placed over the sealer to protect it. The wax is then buffed as needed, encompassing the entirety of required maintenance.
Working with acid and stain can be very hazardous. Safety is paramount. Methyl ethyl ketone (MEK); flammable solvents; acetone; and muriatic, hydrochloric and other acids are some of the nastiest chemicals in construction. Hydrogen chloride respirators, impermeable gloves, protective clothing, goggles, adequate ventilation and elimination of all potential ignition sources (cigarettes, pilot lights on fireplaces and water heaters, and igniters on furnaces) are needed. Residue must be disposed of as hazardous waste.
Professionally applied, general staining prices are as follows:
• Basic one-coat staining: $2-$3 per square foot.
• Multicoat stains with decorative saw cuts: $3-$7.
• Complex saw-cutting and faux staining techniques: $7-15.
• Sandblasting, engraving and other techniques: $15 and up.
New series of books
Taunton Press recently released four home-improvement books in a new series titled "Do it Now, Do it Fast, Do it Right." A series of books centered on "couples DIY projects" initially sounded very intriguing. Anticipating books of stereotypes, industrial-strength bickering and bruising, I jumped right in. And for one very brief but honest moment, the thought may have even crossed my mind that I might obtain potential ammunition for one of my own battles. But then reality rose up and struck me, and I soberly recalled that she always wins the battles, even when she loses.
Alas, no ammunition was found, but in the process I stumbled upon four very good books. "Trim Transformations," "Lighting Solutions," "Storage Solutions" and "Paint Transformations" are the four books in the series so far. More are in the pipeline (for example: "Kitchen Transformations" and "Bathroom Transformations"). Each book fetches $14.95 retail and is also available at www.doitnowfastright.com. For impatient and marginally literate readers, the best part is the number of quality pictures, numbered and perfectly corresponding to the step-by-step text.
Recurring sidebars, such as "Lingo," "Cool tools," "Do it right," "What's different" and "What can go wrong," make for understandable and complete reading.
Residential electrical work is an incredibly difficult subject to write about, as theory and the inevitable exceptions can bog down even the best literature quickly. The authors and editors seem to have a good feel for how far to take each subject, referring the reader to an electrician or the product instructions only where necessary.
Darrell Hay answers readers' questions. Call 206-464-8514 to record your question, |
