If the base of the window septum is smooth or concrete, it is better to perform a notch on it with a drill or fill a special type of plaster net. The old painting must be soaked or removed with a hammer. In order for the mixture to grab the surface perfectly, you need to apply a special type of primer on it. If the mixture is well pestering on the old masonry, then you do not need to create any special preparation. It is also important to start working with slopes at a temperature mark from 15 to 25 degrees. Moisture level — 70%.
