Under-coat - After the primary
coat is dry , second coat or under-coatings are applied on the primed
surface. The color of the under-coat should approximately be of the same
shade as that of the desired finish. It should be a thin opaque film , free
from brush marks.
Under-pinning - This term is applied to the building of new work
underneath an existing structure without disturbing its stability. It may be
necessary when defective foundation of a wall is to be replaced with new
foundation or when the existing foundation of a wall is required to be
strengthened to enable it to carry more loads.
Urinals - They fall under the category of soil appliance and as such
the discharge from urinals is connected to soil pipe either directly or
through a trap provided with gun-metal or bass domed shaped removable
grating.