Comparison of the Economics of on-Site and Off-Site Fabrication of Rebar in Turkey

Gul Polat1 & Glenn Ballard2

1Research Assistant, Construction Management Program, Department of Civil Engineering, Istanbul Technical University, Istanbul, Turkey, Tel: +90-212-285-3737; Fax: +90-212-285-6587; E-mail:
2Research Director, Lean Construction Institute, 4536 Fieldbrook Road, Oakland, CA 94619. 510/530-8656,; Associate Adjunct Professor, Project & Engineering Mgmt. Group, Dept. of Civil and Env. Eng., University of California at Berkeley; and Principal, Strategic Project Solutions.


Most Turkish contractors prefer on-site fabrication of rebar due to several factors most of which are peculiar to developing countries. Therefore, the economics of on-site and off-site fabrication of rebar need to be compared in the project environment, which is subject to most of those factors, and it should be answered whether the strong preference for on-site fabrication is more economical than off-site fabrication in developing countries, namely in the Turkish construction industry. This study presents an economical comparison of the on-site and off-site fabrication practices of rebar by means of a simulation model that makes use of actual data obtained from a trade center project in Istanbul, Turkey. The study suggests that had the off-site fabrication practice been used in the project in Istanbul, the total cost of rebar would have been 1.2% higher than the total cost of rebar in the on-site fabrication practice. This finding also reveals the need for ‘infrastructural’ changes in the Turkish construction industry before its participants can enjoy the benefits of lean construction; a change that may be necessary in some degree for other developing countries as well.


Cut & bent rebar, On-site fabrication, Off-site fabrication, Simulation model



Polat, G. & Ballard, G. 2005, 'Comparison of the Economics of on-Site and Off-Site Fabrication of Rebar in Turkey' In:, 13th Annual Conference of the International Group for Lean Construction. Sydney, Australia, 19-21 Jul 2005. pp 439-447

Download: BibTeX | RIS Format