AEC Myth #147 – Construction Estimating is More Art than Science


Efficient, accurate construction cost estimating is a very detailed profession that is highly dependent upon robust process, definitions, cost databases, terminology / taxonomy, technology, collaboration, and experience.

Granted the AEC industry in the US suffers from cultural issues and lags other sectors in the efficient adoption and deployment of technology, but this will change due to the altered worldwide environmental and economic landscape.

The evolution and convergence of Building Information Modeling (BIM), more efficient construction delivery methods such as Integrated Project Delivery (IPD) and Job Order Contracting (JOC), Capital Planning and Management Systems (CPMS), Computerized Maintenance Management Systems (CMMS), and Computer-aid Facility Management (CAFM), will drive a more collaborative, productive,Architecuture, Engineering, Construction, Operations, and Maintenance industry.

5 thoughts on “AEC Myth #147 – Construction Estimating is More Art than Science

  1. What we are talking about here is prediction. A theory is only as good as the predictions that it allows you to make.

    Conceptual estimating – estimating when all you have is a sketch on the back of an envelope – is inexact – over time the estimate gets firmer and firmer based on ever more detailed design information. Certainly that is the case when you are using the target value design (TVD) approach implicit in IPD.

    Conceptual estimating uses all the definitions, cost databases, terminology / taxonomy, technology, collaboration, experience you refer to – and theory too (otherwise how can it be scientific?) but with a lot more caveats than the later estimates.

    1. Agreed. There are exact and in-exact sciences. Relative to accuracy in construction estimating, various levels can be attained based upon the method employed and result desired, for example:

      – conceptual / model-based estimating +/- 20%
      – system level estimating +/- 10%
      – line item estimating +/- 5%

  2. Your title leads one to believe that estimating is totally science and I don’t think that’s the case. Estimating is certainly less experiential today than it was in the past, but unless the contractor has some of his or her own feedback in the estimating system the results will not be right ont the money.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s