Decks frequently encounter many types of problems depending on their location, function and method of construction. Because deck structures are commonly made of concrete, deck deterioration often comes from a chemical reaction when concrete isexposed to the environment.

Below are some signs that decks are deteriorating or facing problems:

1. Cracking and spalling. Decks may show cracks and rents that indicate severe concrete strain. The strain may be due to sudden freezing and thawing temperatures.

2. Laitance formation. Too much water during concrete mixing can form laitance, which is a thin layer of cement that comes to the surface after the mix is poured.

3. Efflorescence. A white crystalline substance on top of the concrete surface indicates salt residue deposits caused by moisture exposure.

4. Incorrectly-cured concrete surface. Decks should be cured for at least 30 days before deck coatings application; otherwise the high moisture content in the surface can lead to coatings failure.

5. Corrosion of reinforcing steel. Decks use reinforcing bars for better structural integrity. But when steel is corroded, a rust-colored stain appears on the deck surface to indicate that the structural integrity is being threatened.