Research sheds increasingly favorable light on design-build delivery

Sources: Design/Build Institute of America, Washington, D.C.

New Design/Build Institute of America-backed research finds that the design-build (DB) method delivers projects faster and with greater cost and schedule performance than Construction Management at Risk (CMR) and traditional Design, Bid, Build (DBB) alternatives. 

“As our nation continues to struggle with crumbling infrastructure and budgets stretched thin, it’s no surprise that most states have embraced design-build as a better way to deliver projects vital to economic growth,” says DBIA Executive Director Lisa Washington. “Whether it’s a billion-dollar airport or small community library … design-build is clearly a better way to build.” 

Authors of “Revisiting Project Delivery Performance — New benchmarks for unit cost, delivery speed, cost and schedule reliability” conclude that DB projects:

  • Cost 1.9 percent and 0.3 percent less per square foot, respectively, than those using CMR and DBB; 
  • Average 2.4 percent and 3.8 percent less cost growth than comparably scoped CMR and DBB work, respectively;
  • Perform best in terms of schedule growth, exhibiting respective levels 3.9 percent and 1.7 percent below those of CMR and DBB;
  • Are 13 percent and 36 percent faster than CMR and DBB, respectively, during the construction phase; and,
  • From design through completion, are delivered 61 percent and 102 percent faster, respectively, than CMR and DBB.

The Charles Pankow Foundation and Construction Industry Institute (CII) supported the research, which factored data from 80 DB, 79 CMR and 53 DBB projects—131 public and 81 private. Findings build on “A Comparison of U.S. Project Delivery Systems,” a 1998 study benchmarking the three methods. An eight-page “Revisiting Project Delivery” summary, authored by University of Colorado, Boulder Professor Keith Molenaar, PhD and University of Florida Assistant Professor Bryan Franz, PhD is posted here.