Oakland, CA, USA


Board of Directors

Megan Cross-Wilkinson


Megan Cross-Wilkinson has 6 years of experience in the building science industry in the fields of existing building, new construction and forensics/litigation. She currently works in the Oakland office at RDH Building Science Inc., and has managed projects in California, British Columbia and Ontario, Canada. Megan holds a B.A.Sc. in Honours Environmental Engineering from the University of Waterloo in Canada. She is a member of the Association of Professional Engineers and Geoscientists in British Columbia and the California Board for Professional Engineers and Land Surveyors (PELS) in California. 

Bill Gillette


Bill Gillette has been marketing and providing technical sales support for roofing and waterproofing systems over the past 25 years.  Most recently relocating to the San Francisco Bay area in 2010.

Bill lives in Danville, CA with his daughter, Isabella. 

David Markman

Vice President

David Markman is a Project Manager in the Enclosure Engineering Group within Katerra, at Technology Company. David worked for ten years in the Building Technology Division of Simpson Gumpertz & Heger.  He recently moved over and is coordinating the enclosure design, construction, and fabrication of new multi-family prefabricated housing for katerra.  David's expertise lies in the intersection of the water/vapor/thermal envelope with the prescriptive fire related requirements of the building code.  

Rob Worthing


Mr. Worthing is a Senior Consultant at Allana Buick & Bers (ABBAE), specializing in the design, construction administration and general condition assessment of all types of roofing and waterproofing systems. With over 17 years of experience, Mr. Worthing has a unique ability to apply a blend of technical knowledge, field experience, and sound business judgment for each individual project to find the best solution for the client.

Eric Smith

Director at large - Industry

Eric Smith works for Johns Manville in the Preferred Accounts group typically servicing design professionals and building owners.  He has been with JM for over 6 years and has been responsible for product development, sales, marketing, training programs as well as the JM solar energy program.  


Prior to working for JM Eric worked as a manufacturing engineer as well as a design engineer and project manager in the solar energy sector.  He holds a bachelor’s degree in mechanical engineering, a professional engineering license in the state of CA, and an RRO certification from the RCI.

Tom Berger

Director at large - Consultant

Thomas (Tom) Berger has over 29 years’ experience in the design and construction industry.  He is the founding and Managing Principal for DTR Consulting Services.  Prior to founding DTR in 2002, his experience ranged from an Architectural Project Manager, Construction Administrator/ Field Inspector, CM Program Manager, Carpenter, Facilities Planning Manager, Technical Specifier, Forensic Investigator, and Office Leader in various national architectural firms.  Leading an expanding role in building science design & construction validation, he leads his firm in assisting design clients in the selection of appropriate exterior skin wall, roof assemblies, and the almost forgotten area, the 6th side, below grade assemblies.

Tom has received numerous professional certifications and awards, as well being part of numerous award winning projects over the length of his career.

Jonathan Stafford

Director at large - Consultant

Jonathan Stafford is a Senior Project Manager in the Building Technology Division of Simpson Gumpertz & Heger.  Jonathan has 20 years of experience in the investigation and design of major commercial, institutional, and residential buildings for waterproofing issues including roofs, plaza decks, and below-grade spaces.  He consults with architects, contractors, and building owners in the design of the building envelope for new products and to analyze and repair water intrusion problems and construction defects for existing structures.  Jonathan is a licensed Professional Engineer in California and is a Roof Consultants Institute Registered Roof Consultant.

Jerome Jeffers

Past President

Jerome Jeffers has over 30 years of experience in design services for the building industry. His building enclosure experience encompasses a wide variety of project types including educational, institutional, commercial, hospitality and residential.  Jerome is a recognized expert in roofing, waterproofing, and exterior wall consulting.  Mr. Jeffers provides solutions to building weatherization issues and deterioration to building structures. Mr. Jeffers has earned the Registered Building Envelope Consultant (RBEC) certification from RCI, the most prestigious certification for the roofing, waterproofing, and building envelope consultant practice.