Sealer helps prevent pop-outs, weather damage and wear and tear from everyday use. Sealer helps to repel water, dirt, oil and chemicals. It also aids in resistance to abrasion and UV exposure, and deters mold, mildew and algae growth. Concrete is one of the most durable building materials but it does require occasional repair and maintenance. Cleaning and sealing your concrete is just as important as cleaning and sealing your deck or house. Cleaning and sealing maintenance is recommended every two to seven years to ensure that you protect your investment and get the best looking concrete for its maximum life.