Trehan third generation constructors Delhi''s third generation constructors, 6 decades of unprecedented experience in the construction field. Leading government and private contractors with over 100 projects in Delhi and NCR. Over 10 million sq. ft. area in prime locations. Group Housing projects. In-house quality control systems. Footprints in North as well as South India. diversified its operations into the private sector. 3 generations of heritage, experience of over 15 years.