David Hollerbach, a project manager with Zirkelbach Construction, has been designated as a Leadership in Energy and Environmental Design Accredited Professional (LEED-AP) by the Green Building Certification Institute (GBCI).

With more than 30 years of construction experience, Hollerbach has been with Zirkelbach Construction since 2006. He attended Diablo Valley College at Pleasant Hill, Calif., where he studied engineering and construction. He has managed and completed more than $80 million in construction projects