After more than three decades, Tim Barber Architects (TBA) continues to evolve — while staying true to our purpose: creating enduring homes that honor their context, enrich daily life, and draw inspiration from tradition, innovation, and the natural world.

As our projects have grown in scale and complexity, so has our team. We’ve nurtured a studio of designers whose diverse talents are united by curiosity, care, and creativity. This shared spirit of growth has defined our culture and propelled our evolution.

Last year, we proudly introduced David Stone (Director of Operations) and Kelly Becker (Director of Design) as Principal Architects — a milestone that expanded our leadership and deepened our expertise.

We are thrilled to share the next chapter of our story as we welcome two new Principal Architects, Ari Engelman and Katie Peterson-Hesketh.

Ari and Katie, both formerly Senior Project Managers with a combined tenure of 23 years at TBA, contribute immeasurably to our work and culture. Ari brings his deep experience with complex projects, building systems, and strategies to guide our team. Katie’s command of historic architecture and passion for construction integrity ensures that every decision on site reflects our design intent and our homeowners’ visions.

Together with Tim, Kelly, and David, Katie and Ari form a leadership team united by a shared vision of artistic excellence, superb client service, and a collegial team culture. This expanded partnership marks a meaningful milestone for our studio — and an exciting step toward the future. With each project, we’ll continue to learn, listen, grow, and contribute to a better world.

Please join us in congratulating Ari and Katie, and in celebrating this next chapter for Tim Barber Architects.

Ari Engelman

AIA, NCARB
Principal Architect

A New York native, Ari spent the first decade of his career on the East Coast, earning his Bachelor of Architecture from the City College of New York, where he graduated summa cum laude. Early in his career, he focused on institutional projects — primarily educational facilities — throughout the New York area.

After relocating to California, Ari joined Tim Barber Architects in 2015, bringing with him a deep passion for residential architecture. He applies his experience with large-scale projects to a wide range of TBA work, including a 30,000-square-foot new home in Beverly Hills; a three-story hillside guest house and garage for classic automobiles in Bel Air; an artful reimagining of a Beverly Hills estate; and several of the firm’s most complex hillside residences.

A natural educator, Ari shares his technical expertise with the TBA team, mentoring staff on topics ranging from building codes to waterproofing details. He is certified by the National Council of Architectural Registration Boards (NCARB), a member of the American Institute of Architects (AIA), and an active participant in continuing education through the AIA San Fernando Valley chapter. Outside of work, Ari enjoys spending time with his wife and three children.

“When I joined Tim Barber Architects in 2015 as a Project Manager, I admired the traditional, beautiful homes TBA was creating and was thrilled to contribute to them. Now, as a Principal Architect, I’m honored to help shape our future projects, while always connecting to our foundation in vernacular architecture and tailored client care. I look forward to using my experience in architectural detailing and materials for mentoring our team members — while partnering with our collaborators — to create timeless architecture for our clients.”

Katie Peterson-Hesketh

Principal Architect

Raised in Rockford, Illinois, Katie developed an interest in art at a young age — but it wasn’t until her first international trip to Paris, standing in front of the Palais Garnier, that she was inspired to study architecture. After receiving her Bachelor of Science in Architecture from Ball State University, Katie moved to Los Angeles to pursue her career and later received her Master of Architecture at UCLA.

Since joining TBA in 2012, Katie has brought expertise in both modern and historic residential architecture, starting as a Design Associate and now a Principal Architect. While leading projects, she concentrates on translating design intent into the built environment, ensuring that every decision reinforces the integrity of the project and the client’s vision. Knowledgeable about the Mills Act Historical Property Contract Program, she also helps homeowners navigate opportunities for preservation and restoration. Outside of TBA, Katie enjoys renovating her eclectic 1930s home with her husband.

“After 13 years with TBA, I am grateful for this opportunity and am excited to step into this leadership role alongside Tim, Kelly, David, and Ari. With a passion for historic architecture, leading projects will continue to be my focus, integrating details informed by the past while collaborating on inventive and thoughtful solutions that bring our homeowners’ visions to life. Inspired by Tim’s mentorship, I am committed to sharing this knowledge and encouragement with the next generation of aspiring architects.”

Learn more about the rest of our awesome team here.