After the application of the finish coat was completed, we had to wait a minimum of 9 days for the surface to dry. Once the finish coat was fully dried, the facade was power washed with a diluted acid solution. The purpose of the power wash was to remove the thin outer layer of the pigmented cement in order to reveal the aggregate and give the surface more depth and texture. Without the power wash, the brownstone finish would have had a flat, painted look. It’s hard to tell from the photos, but after the power wash, the surface gained a sparkliness that made it look more like natural stone.
The window installers will also come back to calk around the windows to seal up the gap between the window frame and the brownstone finish coat.acid wash, Brownstone Facade Restoration, power wash