Q1: What type of sealer should I use for my concrete countertop or concrete project?
We recommend using a hybrid sealer such as CHENG Concete Countertop Sealer.
Properly sealed concrete should not stain. However, unsealed concrete has approximately the same porosity as limestone and marble. In addition to stain susceptibility, acids (especially red wine, lemon juice, and vinegar) will etch the surface if not cleaned up right away.
Concrete countertop sealers can be segregated into three primary categories: hybrid, penetrating, and topical sealers.
Hybrid sealers seal the concrete by penetrating deep into the concrete surface while allowing a micro-thin layer of protection on the visible surface. This micro-thin layer completely seals the surface without sacrificing the warmth and beauty of the concrete. CHENG Concrete Countertop Sealer (a hybrid sealer) and CHENG Concrete Countertop Wax work together to create the best performing and most beautiful maintenance system available. CHENG Concrete Countertop Sealer effectively protects concrete from acids, stains and cleaning products while our super durable Concrete Countertop Wax protects the sealer from wear and abrasion. Used together, they are an unbeatable combination.
Penetrating sealers seal the concrete from inside, leaving the visible surface with minimal protection against staining and etching. Customers who prefer this method, value it's very dynamic nature. They appreciate how quickly it allows the concrete to patina the same way a cutting board or butcher's block changes with use. Mineral oil and tung oil are examples of commonly used penetrating sealers.
Topical sealers seal the concrete by building a thick, plastic membrane over the concrete. While this method initially protects the concrete against stains and etching, it is exceptionally vulnerable to scratching, peeling and chipping. Epoxy and polyurethane are topical sealers. Be wary of claims that these types of sealers are "stain-proof;" many of them have a tendency to easily peel off of the countertop.
Regardless of which method you choose to use, always follow directions provided by the manufacturer.
Q2: When do I apply CHENG Sealer to the concrete countertop?
Once the countertops have been lifted from the form, or de-molded, you should allow them to sit 48 hours before polishing. After polishing is complete, you can start sealing with CHENG Concrete Countertop Sealer. Simply rinse the surface and start the sealing process while the countertop is still wet. For detailed instructions, follow the directions on the CHENG Sealer bottle, not those written in the Concrete Countertop book, which refer to a sealer no longer available.
There are many methods being used to apply the CHENG Concrete Countertop Sealer. The following method is used in our shop to consistently produce excellent results, while being relatively easy to master. We recommend practicing on a sample piece of concrete before attempting to seal an entire concrete countertop project.
- Work in an area with relatively still air. Breezy or drafty environments can cause the sealer to prematurely dry, creating unwanted steaks.
- Do not attempt to seal under radiant heat or sunlight. Any source of radiant heat will cause the sealer to prematurely dry, creating unwanted streaks.
Supplies you'll need:
- 2 clean jersey rags. We prefer using recycled tee shirts.
- Protective clothing and rubber gloves.
- A bucket or bowl that will hold roughly 1/2 gallon.
- Cool, clean water. If you're working in a hot environment, put a handful of ice in a plastic bag and drop it in your water to keep cool. Warm water will evaporate quickly, and cause the sealer to prematurely dry.
- 500ml of CHENG Concrete Countertop Sealer for every 30 square feet of concrete countertop sealed.
CHENG Sealer Application:
- THE RINSE: Gently wash the entire concrete surface with a clean rag and fresh water. DO NOT "scrub" the concrete. Small particles of grit trapped in the fabric can scratch the concrete's polished surface. Make sure that all dust and dirt are rinsed off the countertop surface before proceeding to the next step.
- THE WATER SOAK: Use a fresh clean rag and saturate the entire concrete surface with clean water allowing water to penetrate for 2 minutes while keeping the entire surface saturated. TIMEOUT TIP: Do not use the same rag you used to wash the concrete surface in Step 1 as it might have particles of dirt or grit trapped in the fabric.
- THE WASH: In a 1/2 gallon capacity bucket or bowl, mix equal parts of clean water and sealer. For example: mix 1 cup of sealer with 1 cup of water. This will create a 50% dilution, which we refer to as the "wash."
- THE WASH SOAK: Using the same rag as Step 2, saturate the countertop with this wash, ensuring that the entire surface stays wet for 5 minutes. It is important at this stage to not allow any area of the surface to dry out.
- THE FINAL WASH: For the final wash, add additional sealer and water to the remaining 50/50 wash at 3:1 ratio. For example add 3/4 cup of sealer and 1/4 cup water to remaining 50/50 wash.
- THE FINAL WASH SOAK: Saturate the concrete surface with "final wash" for 5 min adding additional wash as needed to insure the surface of the concrete does not dry. The concrete surface should appear as if skim milk has been spilled over the entire surface for the full 5 minutes. Add additional wash as needed.
- THE WIPEDOWN: Tightly wring out the rag you have been using in Steps 2-6 and wipe up excess puddling or pooling wash. TIMEOUT TIP: Wipe surface in long straight strokes leaving a paper thin (tissue paper thin) layer of sealer remaining. Do not wipe the surface dry, allow the thin layer of remaining sealer to slowly soak into the concrete.
- THE REPEAT: Apply a second coat (starting again from Step 3) 30 minutes after you have completed the first "wash."
IMPORTANT! The Water Drop Test. After allowing THE REPEAT to dry for 24 hours, place a drop of water on the sealed countertop and allow it to sit for 5 minutes. Wipe up the water. If the concrete has darkened beneath the water drop, the concrete isn't fully sealed: repeat Steps 3-8. Since no two pieces of concrete are the same, some concrete will require additional sealer. Visualize your concrete countertop as a sponge you are trying to fill with sealer, if water will absorb into the concrete (as indicated by the water drop test), so will sealer. We have had countertop sections in our own shop that have required as much as three applications of sealer before it was ready to install.
Q4: How do I remove sealer from my countertop?
If the sealer has been misapplied, or needs to be removed in order to refinish the countertop, use specially formulated CHENG Sealer Remover and CHENG Surface Prep to remove all remnants of the sealer from the countertop. In cases of slight excess build-up or swirl marks, you may want to try burnishing the sealer (before stripping the sealer completely) with the CHENG Burnishing Pad Set to see if this alleviates the problem, then reapply sealer in light coats as directed. For more information about refinishing a countertop, refer to Appendix 4, "Maintaining a Concrete Countertop," pages 190-193, in Concrete Countertops.
Q5: When and how do I apply CHENG Wax to my countertop?
For best results, the CHENG Concrete Countertop Sealer should have a full 24 hour cure before waxing. CHENG Countertop Wax is best applied with a moistened wax applicator in small sections. Since the CHENG Wax dries to a durable hard finish it is very important to buff the wax to a shine while it is still soft. Work in small areas and buff the wax immediately after applying to the concrete.
Q6: How many coats of wax do I apply? How long do I wait between coats?
For a brand-new countertop, we recommend three coats of wax in total. Two coats of wax should be applied prior to installation, and the third coat after installation, to remove any marks and scuffs resulting from installation. For maintenance, one coat applied once a month is recommended for lasting performance and beauty.
Q7: Why do you use a carnauba wax as opposed to beeswax?
Premium carnauba (like that in CHENG Wax) dries to a durable hard finish that is capable of withstanding rigorous daily use. Our experience with beeswax is that it's less workable and never really dries, leaving a smeary greasy appearance. In contrast, carnauba-based CHENG Wax is much easier to work with and is specially formulated for countertops.