General Cleaning for Previously Painted Substrates Surface preparation is a critical step that ensures your coating bonds properly. We make it simple for you with these easy-to-follow instructions for general cleaning. Be sure to read them carefully before you begin, and print a copy so you have them handy throughout the preparation process. Removing contamination Our coatings are designed so that you don't have to completely remove your old coating to achieve a sound bonding and beautiful finish. But you do have to make sure your surface is rid of the following contamination to achieve the proper bonding finish. You'll see we've provided step-by-step instructions for removing the two most common types of contamination: grease/oil and mold/mildew. Type of Contamination Recommended Removal Solution Grease or Oil* H&C® De-Greaser Mold/Mildew** Water/bleach solution Loose paint High-pressure washer Mill scale dirt High-pressure washer Foreign matter High-pressure washer Rust Liquid rust remover Efflorescence High Pressure Washer Severe efflorescence H&C® Etching Solution You'll need: H&C® De-Greaser, a stiff broom, a plastic sprinkling can, a garden hose with a pressure washer nozzle and household bleach. *Cleaning messy grease and oil stains If grease or oil is present on your surface: Thoroughly saturate your surface with H&C® De-Greaser according to package instructions. Using a stiff broom, agitate the entire surface to make sure the H&C® De-Greaser removes all the stains. Let the solution sit for at least 10 minutes. Using a garden hose with a pressure washer nozzle, rinse the surface thoroughly with clean water so that no cleaning mixture remains. Allow the surface to dry for at least 24 hours. Before applying your coating, give the surface one last sweeping with a stiff broom to remove any remaining residue. **Removing mold or mildew If mold or mildew is present on your surface: Using a pump-up sprayer, mix 1 part bleach to 3 parts warm water. Caution: make sure to always pour the bleach into the water so the bleach doesn't splash on you.* Sprinkle the solution evenly on your surface. Scrub the mildewed areas with a stiff broom. Let the solution sit for at least 10 minutes. Using your garden hose, rinse the surface thoroughly with clean water so that no cleaning mixture remains. Allow the surface to dry for at least 24 hours. Before applying your coating, give the surface one last sweeping with a stiff broom to remove any remaining residue. *Wear protective glasses or goggles, waterproof gloves and protective clothing. Quickly wash off any of the mixture that comes in contact with your skin. Do not add detergents or ammonia to the bleach/water solution. Etching your Surface Only if your surface is severely efflorescent must you etch it. Etching is critical to a successful job because etching opens the pores in the concrete so the coating can bond to form a tough shield. You'll need: H&C® Concrete Etching Solution, a stiff broom, a plastic sprinkling can, a garden hose with a pressure nozzle, a piece of dark cloth and a piece of 120-grit sandpaper. Remove all surface contamination, like grease, oil or rust, with a suitable cleaner such as H&C® De-Greaser or a liquid rust remover. Use your hose to saturate the surface with clean water. In a pump-up sprayer, mix 2 parts water to 1 part H&C® Concrete Etching Solution. Caution: make sure to always pour the etching solution into the water so the etching solution doesn't splash on you. Spray the solution evenly on your surface-one gallon covers about 75 square feet of surface space. Agitate the surface with a stiff brush until the bubbling stops,* which should be after about 10 minutes. Rinse the surface two or three times with clean water after using the etching mixture. Rinsing is very critical-use a power washer if you have one. If not, use your hose with a pressure nozzle. After rinsing, rub a small area with a dark cloth. If any residue shows, repeat the rinsing process until the cloth rubs clean. Your surface should now have a texture similar to 120-grit sandpaper-compare the feel of the surface to your piece of sandpaper. If it doesn't have a similar texture, you will have to repeat the etching process. Allow the surface to dry for a minimum of 24 hours. Before applying your coating, give the surface one last cleaning with a stiff brush to remove any remaining residue. *If no bubbling occurs, this means the surface is still contaminated with grease, oil or a concrete treatment, all of which interfere with proper etching. Remove the contamination with a suitable cleaner or chemical stripper, then etch the surface. Dulling Glossy Surfaces You must also clean and dull glossy surfaces from an existing coating before recoating. You can: Thoroughly wash the surface-a one-time cleaning should do the trick-with an abrasive cleanser like trisodium phosphate (TSP), or Sand the surface in a circular motion Testing the coating Before applying your new coating, apply a small test patch of it to your previously coated surface, covering at least 2 to 3 square feet. Allow the coating to dry for one week, then check to see if it bonded properly. If any part of it is lifting from the surface then it did not bond, and you must completely remove the old coating. To remove the coating, you can use a chemical stripper or commercial power blasting. Choosing your coating Now you're ready to apply your coating. Use H&C® Shield PlusTM Ultra Concrete Stain for your particular application.