[1] Univ Free State, Dept Quant Surveying & Construct Management, Bloemfontein, South Africa
[2] Baze Univ, Fac Environm Sci, Dept Bldg, Abuja, Nigeria
[3] Fed Univ Technol Akure, Dept Quant Surveying, Akure, Nigeria
[4] Univ Johannesburg, Fac Engn & Built Environm, CIDB Ctr Excellence, Johannesburg, South Africa
[5] Univ Witwatersrand, Sch Construct Econ & Management, Johannesburg, South Africa