Podcast: Successfully Acid Stain Side by Side Concrete Slabs Poured at Different Times

Tommy C: You’re listening to DIRECTCOLORS.COM/LISTEN Podcast Episode 27, How-to Successfully Acid Stain Side by Side Concrete Slabs Poured at Different Times. If this is your first time listening, then thanks for listening.  I’m Tommy Carter, Sales Manager and Technician with Direct Colors. It may sound odd that concrete poured at different times would not acid stain the same but if you’ve added on to your patio, interior floors or driveway, this podcast is worth the time spent listening! Here to tell you more about why and how to get the best results from your next DIY project is Shawna Turner, General Manager with Direct Colors. Welcome to the podcast, Shawna.

Shawna T:  Thank you.

TC:  Let’s get started. So why does it matter if side by side concrete slabs are poured at different times if you’re planning to acid stain?

ST: Acid Stain is a chemically-reactive stain not just a topical colorant. The stain relies on the minerals available in the concrete surface to react properly and develop the variable, rich color acid stain is known for. Concrete is not mixed exactly the same way every time and the mineral content can vary substantially from one batch to another.  Concrete finishing, especially if a machine trowel is involved, can alter acid staining results dramatically from one floor section to another as well. Keep in mind that exposure to the elements can impact color development on older outdoor concrete slabs. In addition, concrete patches will also stain differently from the surrounding concrete and should be given special consideration before beginning a project. More to this subject than you thought, I suspect.

TC:  For sure!  What recommendations would you make for indoor floors poured separately or patched due to plumbing problems or for carpet tack holes for example?

ST: For indoor floors, making sure the profile is the same across the slab is important. Whether you choose to mechanically profile the floor using a sander or chemically profile with our Hard Troweled Floor Prep, do the same thing everywhere. I recommend reading over page one of our How to Acid Stain Concrete Guide to determine what process will yield the best results for your concrete before beginning. As for concrete patches, they can be tricky particularly if they are in a conspicuous area of the floor. Patches should be sanded flush with the floor before staining. For best results, I would stain and neutralize the rest of the floor first leaving the patch to be stained afterwards so it can be more easily color matched by carefully controlling the stain’s activation time.  Once the patch achieves the same color as the floor, neutralize the stain and move on to the cleaning step. Spray both the patch and the floor with water from a handheld spray bottle to determine when the matching color has been achieved prior to neutralizing.  Keep in mind that we offer topical stains, such as DCI Concrete Dye and Liquid Colored Antique Concrete Stain, to touch up or further accent any difficult areas so don’t worry, there’s more than one path to a beautiful floor.

TC:  That’s good news. What about outdoor concrete?

Many homes have patio and driveway slabs poured at different times. If you want the concrete to be as close to the same color as possible, I suggest applying the stain to the older slab first and leaving it to process for up to 10 hours for maximum color development. The longer concrete is exposed to the elements, the more surface mineral erosion occurs. For this reason, older concrete needs more processing time to achieve optimal color results than a newer slab. After the processing time is complete, neutralize the concrete and rinse so you can get a good look at the color. At this point, apply the stain to the newer slab and leave to process for 2-3 hours.  Using a spray bottle of water, dampen a small area of the old and new concrete and compare.  If it looks like a good match when wet, great. Neutralize and clean the entire slab in preparation for sealing. If not, let the new concrete process for another hour and repeat the test until a color match is achieved. Remember to look at the concrete only when it’s wet not dry. Dry, acid stained concrete does very little to reveal the final color as it will appear when sealed.

TC:  What happens if a color match can’t be achieved with the acid stain? What else can be done?

ST:  As I mentioned before, we have several topical stain options for indoor and outdoor use. I most frequently recommend our Liquid Colored Antique Concrete Stain for patios, driveways and other outdoor concrete. It can be used as a stand-alone concrete stain and often is or as an accent for acid stained concrete. If a satisfactory color match isn’t achievable, Liquid Colored Antique can be applied to blend the colors and create a more uniform final result. Customers often use this to color match on existing stained outdoor slabs where repairs have been made. It’s really an excellent, easy to use product that can renew color, fix problem areas and save customers a great deal of money by avoiding unnecessary tear-outs and refinishing.

TC:  That’s great to hear. Everyone likes to save time and money on home improvement and want to successfully acid stain concrete slabs. Thanks, Shawna, for the helpful tips on how to get the best results when acid staining interior floors and outdoor concrete. I’m sure this will useful information for many of our customers.

DIRECTCOLORS.COM/LISTEN DIY Home Improvement podcasts are produced twice monthly for your enjoyment and show notes can be found at DIRECTCOLORS.COM/LISTEN. Feel free to add the podcast to your favorite RSS feed.  You can also follow us on Twitter, Facebook, Google+ and Instagram. I’m Tommy Carter and thanks again for joining us!