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.