Whether you're finishing your basement floor or looking for something extra on an exterior surface, adding a concrete sealer to your concrete project can protect the surface of the concrete, keep it from staining and create a more durable surface. Concrete sealer should not be applied to concrete until after the concrete is completely cured, which is typically at least 30 days after the concrete is poured.
Penetrating concrete sealers, like silane, siloxanes, silicate and siliconate sealers, are also known as penetrants, reactive and internal sealers. They typically appear invisible. Penetrating sealers seep into the concrete approximately 1 to 4ml below the surface, permanently binding to an element and filling the spaces in between bonded elements, according to Bob Vila, which forms a hard sealed surface to protect the concrete from moisture and other elements. Penetrating sealers are particularly useful in areas prone to heavy freezing where concrete may easily crack due to ice, but concrete sealed with a penetrating sealer can still become easily stained by certain elements, like gasoline or oil.
Topical or fill-forming sealers actually create a topical hard coat over the concrete. Topical sealers include wax, acrylic, epoxy and urethane. Each type of topical sealer creates a different chemical reaction or effect and gives a different appearance. Many topical sealers, such as acrylic paint products, add a shiny, slick look to the surface of the concrete and come in a variety of different colours. Topical sealers can help prevent scratching, scuffing and stains and are often used indoors. A topical sealer should be reapplied every 1 to 4 years to keep the concrete surface completely sealed, according to Bob Vila.
The Ideal Sealer
According to the Portland Cement Association, the ideal concrete sealer would resist stains, provide long-term protection with minimal maintenance, resist heat and not peel or scratch, among other criteria. Each type of sealer available will meet some of these criteria, but neither a topical or a penetrating sealer will meet all. A penetrating sealer will provide long-term protection with minimal maintenance since it binds to the concrete. It will not peel, and penetrating sealers are usually heat resistant. Topical sealers are tough to scratch and won't stain, but they can peel and require regular maintenance. Before you choose a sealer, rank each criteria you want your concrete sealer to meet. Choose the sealer the fits your ideal sealer the closest to choose the best option.