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Serving public and private schools throughout West Coast and Hawaii.

Mae Kawamoto
PE, SE

Structural Principal

Mae has more than 26 years of experience in structural design. She has designed and managed various structures, including custom residences, public and private school buildings, and community centers. She has a special interest in sustainable design and construction and follows LEED certification updates and sustainable practices, making her a natural thought leader for mass timber projects. Mae is thoughtful in coordinating teams to ensure that solutions are efficient and sensible.

Doug Robertson
PE, SE

Structural Principal

During his career spanning 38 years, Doug has managed and directed the structural design of many technologically innovative and diverse projects, including new building design, seismic evaluation and strengthening, performance-based design (including base isolation), and sustainable design. Placing great attention on important project details while executing broader project goals pertaining to construction, budget, schedule, and constructability, Doug has consistently helped owners and architects develop innovative design solutions.

Afsha Ali

Architectural Associate Principal

Afsha has successfully led teams for both new construction and major renovations for various types of projects throughout the Bay Area. She sees every project as an opportunity to enhance the well-being of its users and create a positive impact on the whole community.

Joe Vela

Architectural Principal

Joe has led all aspects of planning, design, and construction. He is well known for his thorough knowledge of projects, positive client interaction, management skills, and understanding the large picture for his clients.

John Diffenderfer

Architectural Principal

John has been instrumental in the success of large and complex school modernizations and construction programs. His clients appreciate his timely and open communication, his willingness to go above and beyond, and his strategic leadership style. John demonstrates his dedication to the environment and decarbonization with his groundbreaking and ongoing work with Net Zero Energy/Emissions projects and advocates for building better and inspiring architects, engineers, and builders to make a positive lasting impact on the planet.

Steve Winslow

General Contractor
Senior Vice President

As Senior Vice President, Steve Winslow drives corporate initiatives for XL on prefabrication, efficiency, and culture. With 30+ years of industry experience, Steve provides high-level stewardship and drives change for XL in large corporate issues. He is a thought leader in the industry and brings people together to effect change. With Steve’s specific expertise in design phase management, he has helped hundreds of progressive Owners get their projects designed and constructed faster and more cost efficiently. Steve is a LEED and DBIA Accredited Professional.

Bryan Rosevear

General Contractor
Project Executive

Bryan has completed over 30 DSA projects. He provides executive oversight during both the preconstruction and construction of the project, making sure that the project-specific work plan and the scheduling are all accomplished to meet client needs. He makes sure that XL’s on-site management team has all the resources to successfully deliver each TimberQuest project.

Matt Larson

General Contractor
Director of Preconstruction

As Director of Preconstruction, Matt Larson oversees all aspects of preconstruction, including cost estimating, cost management, cost studies on alternative materials, methods of construction, value engineering and bid packages. He has been an integral lead on XL’s mass timber projects and has developed expertise related to mass timber construction cost, constructability and procurement. Matt has more than 20 years of experience in the construction industry. He has a B.S. in Construction Engineering from Iowa State University.