Empire State Building – 90 years old, designed and built in 20 months and still ahead of most of us on integration and efficiency 90 years on
By Simon Murray, in News,
It is tempting to argue that the construction of the ESB reflected conditions in the US in the early 1930s and cannot be used to benchmark the construction of tall buildings today. It was built at the beginning of the Great Depression, so there were no shortages of labour or materials. It was also built at a time when there was less concern with the health and safety of the workforce. Seven people were killed during the construction of the ESB – one of them was a young woman in the street below who was injured by a piece of wood that fell from the building and who subsequently died from sepsis. But by making these arguments, we ignore the fact that the design, engineering and construction of the ESB was delivered by an integrated team of experienced architects, contractors and suppliers using the most advanced production methods available at the time.
Fortunately, we have accounts of the construction of the ESB that we can use to explore how this remarkable building was delivered. In 1928 William Starrett published Skyscrapers and The Men Who Build Them which is a personal and detailed account of the design and construction of tall buildings. Starrett was a partner in Starrett Brothers and Eken – the contractor that delivered the ESB. After the building was opened, staff in the contractor’s office wrote up detailed notes of the planning and construction of the building and these have been published by The Skyscraper Museum. Since then there have been several academic studies of the project including a recent paper from Indiana University.
Taken together, these sources paint a picture of an approach to promoting, designing, engineering and constructing the building that is different to the approaches we use today. The promoters were a small group of wealthy men who had intimate knowledge of the economics of tall building and were clear about the outcomes they required. They appointed the architect and the contractor at about the same time and based on capability and experience rather than on price. And they engaged the key suppliers like the Otis Elevator Company at the outset in completing the design of the ESB and planning its construction. In many ways they were following the principles we advocate today through Project 13.
Integrated processes and information
Starrett Brothers and Eken were experts in the construction of tall buildings. It is clear from William Starrett’s book that they understood how every component in a tall building was made and how much labour, materials and plant were consumed in making it. The processes they used to plan and manage the construction of the ESB was based on this deep knowledge and reflected their culture and attitudes. They were respected as experts in their field and, although they sub-contracted large elements of the project, they took responsibility for its engineering and construction. In the accounts of the project, there is no mention of transferring risks to sub-contractors. Starrett Brothers and Eken took most of the risks and expected to keep most of the rewards.
The estimates were developed from first principles using the contractor’s knowledge of the costs of materials, plant and labour. From their experiences of building similar skyscrapers, the contractor knew how much labour was needed to construct a cubic foot of concrete floor or a square foot of limestone cladding and this Labour Unit Cost was a key metric in monitoring construction and assessing whether the project was within budget.
During construction, the contractor employed a team of inspectors that visited every part of the project several times a day and recorded the amount of work that had been done. This information was summarised in the Daily Construction Report and was used to calculate the actual labour unit cost for each element of work. If this number was above that used in the initial costs estimate, the contractor was losing money and if it was less, they were making money. And because the information was available within hours of the work being completed, the contractor was able to take action before any problems became too large.
This approach to monitoring the construction also ensured that in respect of the current status of the project, there was one version of the truth that was available almost in real time. The inspectors measured the work that had been done that day, the staff in the project team consolidated it into a summary report and it was presented to the Superintendent and to Paul Starrett within hours of the work being completed. The whole team seemed to have been aligned towards achieving the targets rather than challenging the data.
To read more from Simon on the Empire State Building click here
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