Concrete is a porous substance made primarily of cement united with fly ash, an aggregate, such as gravel, limestone or granite and a fine aggregate like sand. Once the concrete combines with water a chemical process, called hydration, bonds the components together to create a stone-like material suitable for foundations. The porous nature of the material requires a sealant to bond the surface and prevent cracking from water damage. Treatments for waterproofing vary based on active ingredients. The choice of the proper treatment requires research and professional advice.
Crystalline
Available as a dry powder, Crystalline treatments mix with water to make a texture that sprays or brushes onto concrete surfaces. The sealant reacts with the concrete to cure over a two- or three-day period. The surface must be kept moist to complete the catalytic reaction between the compound and the concrete. This requires periodic misting or a wet burlap covering. The mixture is most effective on newer concrete. Building codes may require an additional exterior basement wall waterproofing in addition to a crystalline treatment. Crystalline treatments work well for concrete used in reservoirs, sewage- and water-treatment tanks and tunnels.
Concrete Sealer X-1
This silicate-based product boasts that it will "last the life of your concrete". The compound chemically bonds to concrete, strengthening and protecting the surface. The treatment is applied with a brush, roller or spray gun at a temperature between 40 and 80 degrees. Concrete Sealer X-1 will cover approximately 200 to 400 square feet per gallon of product, depending on the surface texture. Two coats work best to create a tight bond and provide adequate waterproofing. This compound penetrates porous concrete up to four inches to create a dense, insoluble system with calcium silicate and calcium hydroxide. Concrete Sealer X-1 is nontoxic and environmentally friendly, with no noxious fumes.
The Penetron System
Penetron chemicals penetrate into the capillary tracts of concrete surfaces to provide a permanent waterproofing system. Active ingredients react with the concrete minerals to form insoluble crystals that fill out cracks, pores and voids in the surface. Crystalline growth can take root as deep as one meter into the concrete. This product is environmentally friendly and EPA-approved for potable water. Penetron is available as a dry-shake, trowel applied, an additive mixture for new concrete, as a filler or in spray-on liquid form.
