The stone lining should be made from the bottom upwards
Ornamental Stone Finishing of Arches and Doorways: Design Ideas and peculiar features of Decorative Finishing. : The Stone Lining Should Be Made From The Bottom Upwards
Quote from Article entitled Ornamental Stone Finishing of Arches and Doorways: Design Ideas and peculiar features of Decorative Finishing.:
A doorway finishing with decorative stone does not end on this stage. In order to give it a complete form and to protect against wear conditions, there should be some additional manipulations:Filling paste. It is an obligatory step for any tiling work. In order to fill the joints with mastic properly, you should use a fillet gun. The mixture is not fully injected into the joint: the joints are concealed, the masonry surface is retained.Water-repellent. This stage is required in the process of a front door finishing in areas with unstable humidity level. To protect it from humidity, you can spray a special substance on top of the stone. After drying, it protects the covering against penetration of moisture in its structure, but allows the wall to "breathe".Decorative spraying. It is especially significant in case when you use white gypsum tile. You can change the color shade of the coating, using an airbrush. It is better to use a diluted mixture of color paste. To protect the paint layer- apply an acrylic water-based lacquer. Additionally, you can decorate the door aperture with decorative sparkles applying them locally from the frontal part of the wall.
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