Question

For ideal work, plastering should be applied in three coats- the rendering or first coat of 10 mm, the _____________________ and finishing coat of 5 to 6 mm having a total minimum thickness of 20 mm.

(a) scrubbing or second coat of 10 mm to 6 mm

(b) floating or second coat of 10 mm to 6 mm

(c) painting or second coat of 10 mm to 6 mm

(d) layering or second coat of 10 mm to 6 mm

I had been asked this question in an international level competition.

I need to ask this question from Detailed Specifications topic in portion Specifications, Estimation of Quantities of Materials and Transport of Civil Engineering Drawing

Answer 1

Correct choice is (b) floating or second coat of 10 mm to 6 mm

For explanation: The first coat shall be applied on the prepared raked cleaned and wetted surface by dashing the mortar and floated roughly with wooden float. It shall be kept damp for at least two days. When the first coat has sufficiently set, the surface shall be wetted and a second coat of plaster shall be applied and brought to true even surface and then lightly roughened with a wooden float to provide bond for the finished coat.