Organisation Of U.S. Building Cuts Costs

Press, Volume CI, Issue 29844, 9 June 1962, Page 13

Organisation Of U.S. Building Cuts Costs

The Americans were generally very good at the planning and organisation of work, particularly in the building industry, said Mr F P. S. Lu, a senior lecturer in civil engineering at the University of Canterbury, who returned to Christchurch last evening from the United States.

Much higher wages ruled in the United States than in New Zealand, yet the Americans could still put up buildings at the same cost as here, but at twice the speed. Mr Lu said.

More and more people in the United States were using the “critical path” method of determining building planning and scheduling, said Mr Lu. If used properly here, the method could speed up New Zealand construction, and cut building costs. Mr Lu, who has been away six months, travelled under the W. A. Stevenson award of the New Zealand Institution of Engineers. He spent four months and a half working with the San Francisco contracting firm of Haas and Haynie, and also visited Los Angeles, Denver (for the American Concrete Institute’s convention), Chicago. Pittsburg. Philadelphia. New York, and Washington, and also travelled on to London

As an indication of the speed of American building, Mr Lu quoted a 22-storey apartment block house being built in San Francisco in 18 months, and a 13-storey office block in Los Angeles (15 months).

Mr Lu used both these buildings for his studies in the “critical path” method of planning determination. Method Explained

“The ‘critical path’ controls the comoletion date of a project.” Mr Lu said “Operations included in the ‘critical path’ are all critical operations which control, in turn, the completion date of the whole project.” The first stage of the method was to plan the building by breaking the project down into the many operations—excavation, piling, and so on—which made it up

The second stage was to draw up an "arrow diagram” linking the operations together in sequence—which might consist of about 1000 operations in a 30-storey building—to get a master chart of the whole project.

The third stage was to schedule each operation, giving it a timetable of two or three days, or whatever the time might be, Mr Lu said. The fourth stage was to prepare input sheets for an electronic oomputor, and the fifth stage was the computer's calculation. The output of the computer would show the earliest and latest starting date of each operation, the earliest and latest finishing date, “float times,” if any, and the “critical path.” which was the longest sequence of operations. So far as he knew, the method had not been used in New Zealand. Mr Lu said. For simple jobs, the calculation of the "critical path” could be done manually There was no reason why the method could not be followed in New Zealand, and be of benefit to the building industry.

Besides preparing a paper on the method, Mr Lu has been invited to lecture on it to the Canterbury branch of the New Zealand Institution of Engineers.