Armawall Interior Flat top coat is a third step in the Armawall Texture Coating System with top coats that are designed to give excellent dirt shedding properties, substrate protection, and greater flexibility. Interior Flat is a high build acrylic coating that is usually applied to interior or undercover ceilings and balcony soffits. Armawall Interior Flat produces a high build stipple finish which hides minor surface defects on ceilings.