Blind Nailing means a nailing technique where nail-heads do not have any visibility on the work surface.
Blind nailing equates to a specific nailing technique where the nail-heads are not seen on the surface. This means nails which are not exposed to the elements in case of roofing which has been completed.
This means a way to nail where the nails are gently sunk into the surface of the wall, using putty to cover the same. In this case, the nail-heads will not show as well. This is often used for various types of dwellings or constructions. Hence it is strongly connected to the real estate sector.