Remove all furniture, decorations, plants, pots, toys, and any other items you have on your patio. You need a clear surface to work with to ensure your patio is cleaned properly and painted evenly. Cover plants and landscaping near the patio with tarps to protect them from cleaning solutions and water run-off. Clean out the crack(s) with a wire brush. Vacuum or blow out any dust and dirt, or use a broom to make sure the crack is clean. Fill the crack with masonry crack filler. Depending on the brand, either apply the filler with a scraper, or a caulking gun (if necessary). To fill deeper or wider cracks, fill them by a quarter-inch (six mm) at a time. Allow the product to dry between applications according to label instructions.  For best results, repair cracks in completely dry concrete. If the concrete is slightly damp, dry with a blow dryer or heat gun, then wait fifteen minutes. If more water has seeped into the crack, protect the concrete from water until it dries on its own.  Sand down grout- or concrete-based fillers with fine sandpaper, then clean the area a second time. (Do not sand self-leveling or latex-based sealants). Pull out anything that has grown on the surface of the concrete, and spray the patio down with a pressure washer if you have one. If you don’t have a pressure washer, remove what you can by hand, sweep the patio, and hose it down to remove any excess clumps, dirt, or debris.  Borrow a power washer from a neighbor or rent one from a tool rental company or home and building store if you don’t have one of your own. A pressure washer will be very useful for cleaning and rinsing your concrete patio prior to painting. To clear a large amount of vegetation, spray a broad-spectrum herbicide such as glyphosate (Roundup) at least two weeks before cleaning. Concrete can absorb and trap dirt and grease. To ensure it is completely clean and has a fresh surface for paint to adhere to, scrub the concrete with a product that will draw substances out, such as trisodium phosphate, muriatic acid, or phosphoric acid. These products will also help remove old paint, which needs to come off before repainting.These products are not designed to remove old paint.  Read all safety information before you begin. Many concrete cleaning products require everyone in the area to wear rubber gloves, eyewear, masks, rubber boots, and protective clothing. Rinse the concrete so the surface is wet. Apply your cleaning solution (acid, trisodium phosphate, or other cleaner) as per the manufacturer’s instructions. Scrub the concrete with a stiff brush. If you use muriatic or phosphoric acid, this process is called etching, and will ensure the concrete has a sandpaper-like texture that paint will stick to better. Etching should be done before painting new or bare concrete. It is best to use a power washer, as this will wash away excess debris, old paint, and efflorescence, a whitish salt deposit that forms on surfaces like concrete and stucco. If there is still any old paint left on the concrete, scrub it with a wire brush and continue power washing until it’s gone.  If you used an acid solution to etch the concrete, neutralize the pH on the surface by sprinkling baking soda over top before rinsing.  Especially after etching, be sure to rinse the concrete with water until no chalky powder comes off the surface when you touch it with your fingers.
قم بإخلاء السطح. أصلح الشقوق الموجودة بالخرسانة. قم بإزالة الخس الطحلبي والجذور والكرمات. نظف السطح الخرساني. اغسل السطح بماء متدفق.