How to: Applying Acid Stain and Concrete Sealer During the Summer
Acid Staining Outdoors in the Summer
Concrete temperature and wind conditions often determine success or failure for an acid stain project. Hot, dry conditions can cause acid stain to prematurely dry before properly reacting with the concrete. How hot is too hot? Concrete shouldn’t be more than 75-80F for best staining results. Dry, windy conditions can wick the moisture from the concrete leaving a “blotchy” appearance behind particularly when using both light and dark colors.
Summertime Acid Staining Tips:
• Apply acid stain either late in the evening or early in the morning when concrete temperatures are at their lowest.
• Lightly dampen not flood before applying acid stain to outdoor concrete to add moisture and prevent premature drying.
• Direct sunlight and ambient temperature are not the same. Lay a thermometer on the concrete surface and cover with a towel. If after 4-5 minutes the temperature is greater than 80F, do not stain.
Sealing Outdoor Concrete in the Summer
Finding the right time of day to apply concrete sealer during the summer months can be a challenge. Sealers should be applied when the concrete is at its lowest temperature either early in the morning or late in the evening. East facing concrete should be sealed later in the day and west facing early in the morning. Colored concrete in direct sunlight, especially dark browns and black, could be several times hotter than the ambient temperature and just a few minutes of sunlight will raise the surface temperature very quickly. When the slab is hot, air passes thorough the concrete at a faster rate causing more air bubbles and the sealer resin often dries before the solvent or water can completely evaporate.
It’s particularly difficult to seal outdoor countertops in the summer. Countertops are thinner than concrete slabs resulting in faster heat up in direct sunlight. Test the temperature using a thermometer before attempting any sealer application.
Summertime Sealing Tips:
• Apply sealer in the early morning or early evening depending on the location of the concrete
• Avoid applying sealer to concrete in direct sun, especially countertops
• Do not apply to concrete hotter than 85-90F