O'Neil Architects Staff

Thomas J. O'Neil, Architect, AIA

A licensed and registered architect in Virginia and the District of Columbia and member of The American Institute of Architects, Tom has over 32 years experience in design and construction. After earning his Bachelor’s of Science in Architecture at the University of Virginia and Bachelor’s of Architecture at the Catholic University of America, Tom became a licensed architect in 1986, and started the company in 1988 from a home office in Reston, Virginia. 

Clients initially included referrals from Tom’s former employers, small contractors, and family friends. Architectural drawings were hand rendered. In 1992 the business moved to office space over the garage in a new custom home in Loudoun County, Virginia, designed by Tom. In 1994 architectural drawing moved from being hand rendered to computer generated, using CAD programs for both 3d modeling and construction drawings. In March 2007, O’Neil Architects moved to its current location at 110 Loudoun Street SW in downtown Leesburg, Virginia.

Tom currently serves as chairman of the Town of Leesburg Commission on Public Art (COPA) and is a member of Friends of Leesburg Public Art (FOLPA).  He was recently awarded The Town of Leesburg’s 2018 Business Award for Public Art which celebrates a business, organization, or individual that contributes to the development of the Town’s public art program or actively supports the arts within the Town of Leesburg.  Tom also performs as a singer and guitarist at small music venues around Loudoun County.

Payton Bridge – Associate Architect

After earning his Bachelor of Architecture degree at Virginia Tech in 2013, Payton joined O'Neil Architects in August 2014 as an Associate Architect and relocated from Salisbury, Maryland to Leesburg, VA. Payton is a skilled designer and 3d modeler and is involved in all stages of many of our projects, developing design solutions, creating detailed 3d models, developing working drawings and providing construction contract administration services.

Katie A. Bonanno - Associate Architect

Katie earned her Master's of Architecture at the University at Buffalo in May 2010 and joined O'Neil Architects in July 2010. She is involved in all stages of many of our projects, developing design solutions, creating working drawings and providing construction contract administration services. Katie provides much of our in-house Interior Design expertise and can work with you to select materials, furnishings, accessories, appliances, lighting fixtures, colors, fabrics, and finishes.

Evan Pergrim – Associate Architect

Evan earned his Bachelor of Architecture degree from Florida A&M University in 2014, relocated to Northern Virginia in 2015 and joined O'Neil Architects in April 2018. Evan is also involved in all stages of our projects, developing design solutions, creating detailed 3d models, developing working drawings and providing construction contract administration services.

Diana O'Neil

Diana manages the financial, marketing and information technology areas of the business and actively maintains the company website. Diana received her Masters of Business Administration from the George Washington University in 1985 and joined O'Neil Architects in 1999 after a twelve-year career at IBM.