Question

Economy can be achieved in doors, windows, ventilator by:

(a) No frame

(b) Less width

(c) Steel frames

(d) Less height

The question was asked by my college professor while I was bunking the class.

This is a very interesting question from Cost Effective Construction Techniques topic in chapter Building Construction of Basic Civil Engineering

Answer 1

Right answer is (c) Steel frames

To elaborate: Doors, windows and ventilators are openings in the wall that are held on a frame. Not using a frame is economic, but not very aesthetic.  Using concrete/steel frames instead of wood can help in reducing cost.