The porous nature of concrete allows fluids to cause permanent staining on porch surfaces as water seeps into and cracks newer poured concrete porches. Applying sealant creates a protective barrier, keeping the concrete stain- and crack-free. Proper application is vital to ensure the sealant evenly covers the entire surface of the concrete porch. Every thin or missed section -- no matter how small -- will result in damage.
Remove debris from the surface of the concrete porch by sweeping it thoroughly with a broom. Ensure the concrete is free of all debris before continuing.
Pour water-based concrete cleaner in a hand sprayer. Stop pouring when the cleaner level reached the "Full" line marked on the outside of the sprayer container. Pump the handle to pressurize the sprayer. Wet the concrete porch with water from a garden hose. Spray concrete cleaner on the wet concrete. Scrub the area with a stiff-bristled brush. Wash the cleaner from concrete. Pour the remaining cleaner back into its container. Allow the concrete to dry for 24 to 48 hours.
Fill the hand sprayer with concrete sealer. Spray sealer around the edges of the concrete porch. Spread the sealer around the edges of the concrete with a paintbrush.
Spray sealer on the remaining area of the concrete porch. Spread the wet sealer across the porch floor by rolling a paint roller across the floor in long, even strokes. Allow the sealer to dry for two to four hours. Apply a second application of sealer to the floor, if needed. Allow the porch floor to dry for 24 hours.