Sealing Old Exterior Concrete

The building material is not good at resisting marks and stains as it ages, although concrete is durable and long-lasting with no specific treatment. Adding a protective seal to coat your concrete-based projects can help prevent stains from engine oil dirt, mildew and other fluids.

All Sealed Up

Make any necessary repairs, like smoothing rough spots, filling cracks or repairing weathered segments before sealing the concrete surface. Before applying a new one, if the older concrete has been sealed, the sealant should be stripped. Whether it has been sealed it has to be cleaned thoroughly prior to sealing or dirt, any stains and dirt will be trapped beneath the sealant. You can force use trisodium phosphate and a clean brush to remove stains, or wash off the concrete. Rinse the surface well and allow it to dry before using the sealer. Follow the manufacturer’s instructions for spraying or dispersing the sealant. The sealer in coats, allowing it to dry between each coat.

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