To Paint Concrete Rendered Walls, you have to determine whether cement or acrylic render was used on your concrete walls. After that, apply a coat of sealer to the concrete rendered wall if the render is made of acrylic. You need to let this to dry for several hours. Once dry, you must run your hand over the finish and feel for an abrasive or smooth finish. If it still feels fairly rough, you should apply a second coat of sealer.
You can let the second coat to dry overnight. Then, Use a power rotary sander with heavy gauge paper on walls that are rendered with cement. You have to Dust off the excess with a clean paintbrush and apply the first coat of sealer. You need to let several hours of drying time between each coat. Next, apply the concrete paint in your chosen color using a brush or a roller.
You must let it to dry for a couple of hours before applying the second coat. Once the second coat has dried, you should check the surface from a variety of angles to see if the paint requires any touch ups. Forth, enjoy the look of your painted concrete rendered walls. If outside, you can wash them off by simply using a garden hose.