April Hughes, AIA, NCARB, LEED AP BD+C is Owner and Managing Principal at HPZS. A graduate of the University of Kansas, in 2014 April was named AIA Chicago Dubin Family Young Architect of the Year, and in 2013 she was the recipient of the AIA Illinois John Wellborn Root Award. Hughes is leading the firm, starting a new chapter in it’s history as a woman-owned business by embarking on a path to design and preserve a sustainable future for the Chicago community.

April has extensive sustainable design experience, highlighted by the completion of three LEED Platinum and one Gold project. She has collaborated on the creation of the Smart Code Sustainability Module, the City of Chicago’s Public Building Commission Water Reuse Manual, as well as the recently published Living Cities: Transforming APEC Cities into Models of Sustainability by 2030.

A leader in Chicago firsts, April collaborated on the design of Chicago’s first greywater system for a single-family residence, and one of the first variable volume vent hood installations for a restaurant kitchen in the City; her work has resulted in Chicago’s first net-zero single-family residence (Yannell Residence) and first net-zero commercial building (Harmony House).

April’s work has appeared in the Chicago Tribune and reviewed by architectural critic Blair Kamin, Chicago Realtor, Shore Magazine, the Living Well Network, ABC7News Chicago, Elle Décor and numerous other publications. She was a featured interview by Geoffrey Baer on WTTW-Chicago (PBS) for the Yannell Residence on “Chicago Tonight.”

April is a contributing editor to She has contributed to the best-selling Sustainable Urbanism: Urban Design with Nature to the American Institute of Architect’s Young Architects Forum (YAF) Connection Magazine. She was a finalist in the national USGBC Emerging Green Builders Design Competition (2003) as well as AIA Chicago’s ReThink/ReDesign/ReCycle Competition (2004).

In her free time, April unwinds by reading, gardening and painting. She acts as the office’s social media maven.


Henry Zimoch, AIA is a Senior Principal at HPZS, and is the firm’s Director of Historic Preservation. A Chicago-area native, he graduated from the Illinois Institute of Technology in 1975 while working for the firm of Dubin, Dubin Black & Moutoussamy. Leaving DDB&M in 1978 he spent three years working for Marvin Ullman & Associates, and another three years as a field superintendent for a boutique general contracting company. Henry opened his own office in the Monadnock Building in 1984 and in 1991 joined Wilbert Hasbrouck, James Peterson, and Jay Sirirattumrong to form HPZS.

In his 23 years with the firm, Henry has continued to develop his expertise in historic preservation, renovation, and restoration through his work on some of the Midwest’s most significant historic structures. These include the People’s Savings Bank by Louis Sullivan (winning both The President’s Historic Preservation Award and the Chicago Chapter AIA Honor Award), Soldier Field, the Civil War era Seneca Grain Elevator, and the John Christian Residence by Frank Lloyd Wright.

Henry Zimoch has been a member of the AIA for over 25 years. He has written several magazine articles regarding the firm’s work. He also accepts speaking engagements that focus on the architecture and history of Chicago.

Henry is an avid collector of Frank Lloyd Wright and Prairie School books and memorabilia that extend from the sublime (the rare 1972 Japanese book by Nobumichi Akashi Frank Lloyd Wright in Imperial Hotel) to the mundane (a box of matches from the Imperial Hotel with a faux FLLW design). He also enjoys backpacking and films, including the early history and development of film technology and the movie industry.


Sally Guregian, AIA is a Senior Associate and Senior Project Manager at HPZS. She obtained her Bachelor of Science and Master of Architecture from The University of Michigan, with a concentration in Historic Preservation and Conservation. Sally joined Hasbrouck Peterson Associates in 1988, and has remained with HPZS since its inception 1991.

In her over 26 years with the firm, Sally has contributed her historic preservation expertise to innumerable projects, and is a trusted resource for the creation of nuanced construction specifications, historic structures reports, National Register nominations and Federal Historic Preservation Tax Incentives program submittals. Sally has been responsible for projects as diverse as preparation of Historic Structures Reports and a comprehensive Materials Conservation Analysis and repair handbook for the 42 historic structures at Great Lakes Naval Training Station, the restoration of the copper roof and front entrance of the Museum of Science and Industry, rehabilitation of the Gross Point Village Hall as the Wilmette Historical Museum, architectural improvements and mechanical upgrades to the State of Illinois’ Metamora Courthouse, replication of the American era Fort at Fort Massac State Park, and repair of the façades of the historic Palmer House Hilton in Chicago and Downtown Atlanta Marriot Residence Inn in Atlanta, Georgia. In addition, Sally has served as historical consultant on numerous projects throughout the Midwest, including restoration of the Dubuque Shot Tower.

For the last 11 years, Sally has served on her neighborhood’s Covenants, Building and Zoning Compliance Committee, first as a plan reviewer and for the last several years as committee chair. She also serves as a parent volunteer in Northbrook’s Boy Scout Troop 64.

Sally continues to do inspection drops for the firm, high in the air inspecting building facades around the country. When she’s not in the air, Sally’s spends her free time deep in the pages of the world’s on-line archives, researching her family’s far-flung history and the life of the Armenian people in the Ottoman Empire.


Sheila Schaefer, AIA, IIDA is a Senior Associate and Senior Project Manager at HPZS. A registered architect with Undergraduate and Masters of Architecture Degrees from the University of Illinois, Champaign-Urbana, as well a Professional Diploma in interior design from the Harrington Institute of Interior Design, she is HPZS’s resident registered interior design specialist.

Since joining the firm in 1994, Sheila has been the firm’s leader in projects where architecture and interior design play a significant role in project delivery. The partnership of her architectural skills with expertise in space planning, and interior finish and furniture selection has resulted in the successful completion of a number of residential and commercial projects, including several historical renovation projects where specific attention to the existing historic architectural elements have been accentuated to provide an interrelation between the existing and the new. Sheila’s work includes the adaptive re-use of an existing 150 year old barn to a community center at Vehe Farm in Deer Park, master planning and renovation of Resurrection Lutheran Church, interior design of the Fort Massac State Park’s Visitor Center and Prairie Avenue Bookshop, interior renovation and additions to several residential properties, and interior build-out of various corporate offices such as Edison Credit Union, Land America, and Eaglemark Financial Services.

During Sheila’s twenty years at HPZS, she has held a teaching position at the Harrington Institute of Interior Design for interior programming where she helped guide students in the understanding of the fundamental concepts of design, code research, and spatial planning. She is both a member of the American Institute of Architects and the International Interior Design Association.

Outside the office, Sheila has over 15 years of experience in the ceramic arts and enjoys volunteering her time at a local Chicago ceramic studio where she assists students in the execution of handmade ceramic art, specializing in wheel thrown sculpture with Art Nouveau styling. She has also actively participated in the study of martial arts with a specific focus in weaponry training and teaching.