About timelines and estimates in construction projects
"Managers" connected with a mega construction project for my university are targeting a timeline of less than 3 years for move-in to the facilities of about 1.5M gross square feet (gsf) area which is a large mix of buildings of engineering and science departments, offices, classrooms and housing etc. Their optimism defies the past experience on the same project where for about 0.9M gsf area of similar nature the project has taken more than 5 years, and yet the move-in date is (hopefully) one year from now.
I have been sceptical about such optimistic estimates, and have been researching about the timelines and completion data about similar projects. In fact, in one of my earlier posts I tried to highlight some statistics about project failures and some of the key reasons for such slippages as observed by many project managers and organisations across the globe. Unrealistic estimates about complexity and real quantum of work is one of the major reasons for failure. Consultants (and even sponsors), in their bid to grab the project to their portfolio, often underestimate the complexity and ignore critical risks facing the project. One direct consequence of such approach is highly optimistic/unrealistic timelines.
In this post I'm just jotting down a small but useful piece of information that I found about project durations as has been observed in academic institution infrastructure building projects. Table-1 below presents the relevant data about typical project durations (from programming phase of the project to move-in). Typically, programming phase in construction projects is right after the scoping and feasibility phases and before one starts with schematic designs.
Table-1 (Typical Project Duration. Source: Stanford University PDP Manual, 2010)
|Sample Project Type||Typical Project Duration||Typical Construction Duration|
|Large science/medical project (> 25k gsf)||3–5 years||2–3 years|
|Large office/classroom project (> 25k gsf)||3–4 years||1–2 years|
|Large housing project (> 25k gsf)||2–3 years||1–2 years|
|Large renovation (> 25k gsf)||2–4 years||1–2 years|
|Small new buildings||2–3 years||1–1.5 years|
Though each project by definition is unique, performance data from past projects of similar nature are always useful to consider during estimation. Luckily, in the Internet age finding such data is not difficult; you will be able to find such data in project management reports and handbooks. Despite all such data being easily accessible, it surprises me when even experienced project managers and sponsors choose to ignore it in their planning.
I will close by quoting Georg Hegel: "We learn from history that we do not learn from history."