SEVEN: SEAL THE COUNTERTOP

• Always indoors or in the shade when possible.
• Away from moving air.
• In a dust-free location.
• Avoid anything that will cause the sealer to dry too quickly. If the sealer dries too quickly, this can cause streaking when it’s being wiped off.

Step 2 – Dilution

• 30% sealer : 70% water
• 100% sealer is difficult to work with, so we apply a lot of thin coats.
• The amount of sealer you need will depend on the size of your project. CHENG Sealer comes in two sizes, 4 Liter (200-400 square feet coverage) and 500 mL (30-50 square feet coverage).

Step 3 – Soak With Water

• Rinse the concrete thoroughly with clean water, using a 100% cotton cloth that won’t scratch the surface.
• If the concrete you want to seal has been sealed and waxed before, remove the wax with mineral spirits.
• Use a fresh rag and wipe down the surface and edges of the countertop with water until the whole countertop darkens.

Step 4 – Apply Sealer

• Sealer is best applied with a lot of thin coats, like spray-painting. It is difficult to work with a 100% sealer concentration. Diluting it with tap water will make it easier to apply with less chance of the sealer streaking as it dries.
  •    Soak the rag in the sealer dilution (30% sealer to 70% water) and wipe down the countertop, starting with the edges.
  •    Liberally apply sealer to the whole piece, and agitate it with the rag for about 5 minutes.
  •    Let the sealer soak into the concrete, applying it uniformly and methodically, making sure you don’t miss a section. If the piece is big, work quickly before the sealer starts to gel. At that point, you’ll be smearing the sealer and causing streaks.

Step 5 – Wipe Up Sealer

• Wipe up the sealer with the same rag, and wring it out back into the bucket of sealer dilution.
• The idea here is to leave a very thin and uniform layer of sealer on the surface, not to dry the countertop completely.
• Avoid streaking by working quickly and methodically and in a shady, cool place.
• For “new” concrete, you’ll apply sealer like this anywhere from 3 to 6+ times until the concrete doesn’t darken anymore when water is dripped on the surface.

Step 6 – Water Drop Test

• After the concrete has been sealed and allowed to dry overnight, you can perform a water-drop test to check the sealer.
• Pour water on the countertop and let it sit 10 minutes.
• Soak up the water, and if the surface has darkened, it isn’t fully sealed. Repeat Steps 2-4 until it passes the water-drop test and the surface doesn’t darken.
• When the countertop is fully sealed, the sealer can be burnished with diamond infused hurricane pads to remove any streaks or to adjust the surface sheen.