Because many sealers can be applied 'same day', many concreters think that sealers can be applied the next day. This seems logical because the concrete should be drier. However, it is WRONG!

When new concrete (including pattern or Faux Brix) is poured and machine or hand finished until it is firm and resistant to light foot traffic, it can be sealed with 'wet on wet' or same day sealers. These sealers are often described as "cure & seal" products because they assist moisture retention improving the curing process.

On the first day the new concrete is warm and absorbent and has no concrete dust, efflorescent salts, oil, or other contamination on the surface. Provided the surface has no liquid water on the surface the new sealer usually penetrates into the concrete guaranteeing adhesion and durability.

On the second day (next morning) the concrete is usually moist, cold, and not as absorbent. There is also a possibility that it is affected by efflorescent salts, powder, and dirt. The concrete at this stage is too green to acid etch or high pressure clean, and therefore additional surface preparation cannot be undertaken.

Subject to weather, temperature, concrete strength, and other factors the concrete may not be ready to prepare for several days in summer, and up to a week in winter. Concreters who apply sealers on new concrete on the second to fifth days take some risk that future adhesion problems will develop.

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