TANDEM noun tan· dem | \ ˈtan-dəm:
Two or more people working together to achieve a common goal.
Tandem
Tandem is a team of hard working real estate developers, construction managers, architects and property managers. We develop lasting relationships built on trust, quality, and focusing on the long term. We encourage autonomy and a culture where the best ideas win.
OUR TEAM


Tony Andrews

Dimitri Nassis

Christopher Walsh

Sean Staunton

Jeffrey Hreben

Justin Kleifield

Pat Cox

Kevin Henning

Mike Zemanek

Tianyi Pan

Michael Prohov

Glenn Miles

Chris Wood

Peter Szczelina

Taylor Schaub, AIAS, Assoc. A.I.A

Kaitlyn O’Callaghan

Ryne Malonzo

Manuel Hernandez

Tony Andrews
Tony Andrews founded Tandem in 1997, and is the Director of Construction at Tandem. He manages the site superintendents, project managers, and estimators. He enjoys site and field work, value engineering, operations management and lean processes, as well as business development. Having been in the industry for 27 years, his favorite part is being able to solve problems and seeing the confidence clients have, knowing they’ve made the right decision in choosing Tandem. Tony was born and raised in the Chicagoland area, and now lives in Park Ridge with his family.

Dimitri Nassis
Dimitri Nassis received his bachelor’s in Psychology and Philosophy from the University of Illinois at Chicago and a Construction Technician Certificate from Triton College. After graduating, he spent a decade in the financial industry as an options trader at the Chicago Board of Trade and the Chicago Board Options Exchange. He left the trading floor and followed his lifelong calling by entering the world of construction and real estate development. After reconnecting with childhood friend Tony Andrews, he helped found Tandem in 1997 and began Tandem’s journey as a developer. In addition to real estate, Dimitri also helps guide the company’s marketing and property management teams. Most recently, Dimitri was instrumental in helping secure Tandem’s largest and most noteworthy development and construction project, MODE 2501, which is a $23M, 78-unit mixed-use building in Logan Square, completed in early 2017.

Christopher Walsh
Chris Walsh received a Bachelor’s Degree in Architecture from the University of Illinois at Chicago and is a licensed Architect in Illinois, Wisconsin, Indiana, Michigan, and Colorado. Prior to becoming a partner at Tandem, he worked for one of the nation’s largest architecture firms and then became the Vice President of Architecture for a national home builder. Additionally, Chris has a background in construction, having worked in the field throughout high school and college. Chris manages the architecture team and serves as the Principal Architect at Tandem.

Sean Staunton
Sean Staunton received a Bachelor in Public Service from Northern Illinois University. Prior to joining Tandem, he worked with Lettuce Entertain You, Brinker International, and was a realtor at Coldwell Banker. His role at Tandem includes project management, client relations, and business development. He is also the warranty service and OSHA systems manager. His expertise is in designer interior build-outs, including new construction, remodeling, and landscape/exterior space construction. Sean is the Director of Special Projects and Service, helping serve clients and building associations beyond the completion of their projects.

Jeffrey Hreben
Jeffrey Hreben received his Bachelor’s in International Studies with an emphasis in Economics from the University of Chicago. He earned a Master’s in City Planning from the University of Pennsylvania and a certificate of Real Estate Development from the Wharton School of Business. Prior to joining Tandem, he worked at Progressive Housing Ventures, a residential construction and development firm in Philadelphia that capitalizes on transit-oriented development opportunities. His work at Tandem focuses on various real estate development initiatives, including zoning and entitlements, financial underwriting, investor relations, and project management.

Justin Kleifield
Justin joins Tandem as our Development Manager and will be working with the Tandem Development team. Most recently Justin was with Stage Equity Partners in acquisitions and asset management. While there he was involved in vetting new medical office opportunities and assisting in all manners of transaction work. Before that he was at Dayton Street Partners and Lakeshore Management where he honed his skills in underwriting, market research, development, and operations after completing his BA and Master’s in Accounting at Indiana University. Justin brings a wealth of experience that will be a great complement to our work here at Tandem. Outside of work he’s an avid IU basketball fan and be sure to ask him to tell you about his love of travel or what how he’s hitting the golf ball.

Pat Cox
Pat grew up in southern Indiana and graduated from Purdue University with a B.S. in Construction Engineering and a minor in Management. After working on a variety of complex projects for a large general contractor in Los Angeles, he moved to Chicago and now lives with his wife and two kids in Elmhurst. He joined Tandem in 2015, is a LEED Accredited Professional and is OSHA 30 certified. Pat led the field operations for the recently completed Avenir tower and is overseeing the construction of the new 20 story Avra building. His expertise in scheduling, site logistics, LEAN Construction principles and team communication greatly contribute to the success of his projects.

Kevin Henning
Kevin was born and raised in Green Bay, Wisconsin and moved to Chicago after attending college in Cleveland, Ohio. He has a Bachelor of Science in Civil Engineering from Case Western Reserve University as well as a Master of Science in Civil Engineering from Illinois Institute of Technology. He is a licensed Structural Engineer in Illinois, New York, and Arizona and has been involved with the design and construction of over 2,000 apartments, condos, and student housing units, along with healthcare, cultural, higher education, and sports facilities. He currently acts as Project Executive to manage all aspects of new construction and renovation projects. His expertise is in budgeting, scheduling, construction logistics, value engineering, and coordination of building systems. His favorite part of his job is developing innovative construction solutions through collaboration with design professionals and subcontract trades.

Mike Zemanek
Mike hails from the South suburbs of Chicago, and has lived in Chicagoland for most of his life. He studied Construction Management at Bradley University and currently acts as a Construction Manager at Tandem, dealing with the day-to-day supervision of the construction jobsite. He makes sure that quality is being controlled so that clients are receiving the best product possible. His favorite part of the job is that every day is different; there are always new challenges that require thinking outside of the box. The end product also gives him a sense of pride, as he has contributed to the ever-changing cityscape. Mike loves spending time with his kids and playing a round or two of golf in his free time.

Tianyi Pan
Tianyi was born and raised in Ningbo, China. He earned his Bachelor’s Degree in Civil Engineering in China and his Master’s Degree in Construction Engineering and Management at Illinois Institute of Technology. Prior to joining Tandem, he worked as a field engineer for Ningbo Construction—a regionally known developer and GC focusing on site operation for large-scale high-rise projects. He is a LEED Accredited Professional and also OSHA 10 certified. At Tandem, his key tasks include project procurement and project management. His favorite part about his job is keeping trades within the clients’ budgets and meeting the clients’ high-quality expectations.

Michael Prohov
Michael is an architect and project manager supporting both the development and construction teams. In addition to practicing architecture, he has experience in the field as a lender’s inspecting architect and as a general contractor. He performed his undergraduate studies at the University of Illinois at Urbana-Champaign with his third year in the Study Abroad at Versailles Program. He later achieved a Master’s in Architecture at the University of Oregon in Portland with a focus in Urban Design and Development and landscape infrastructure. He is licensed to practice in Illinois.

Glenn Miles
Born in San Diego, California and raised in Santa Barbara, California, Glenn joined the U.S. Army after High School and served in the 2nd Ranger Battalion for 4 years at Ft. Lewis in Washington State. He met his wife while stationed in Washington State and this was where they were married and lived for 17 years. They currently reside in Valparaiso, Indiana. They have two grown Children (Andy, 26 and Olivia, 22) who both live in Chicago.
Glenn received his BS in Civil Engineering from St. Martin’s College in Lacey, Washington and holds professional engineering licenses in the states of Washington and Iowa (both are inactive status). Prior to Tandem, Glenn has been in the construction and industrial field working as Division Manager at Ryan Companies, Midwest Regional Manager at Walbridge Industrial Process, and as the Vice President of Operations at Power & Sons. His focus is on Public Contracting and the Design-Build process.
As Tandem’s Director of Public Projects, Glenn’s expertise reaches into the operational aspects of construction, managing the business, and strategically focusing on key issues. His favorite part of the job is working with younger people just starting with their careers. He says “There is so much to learn and be taught about what we do that you just cannot get in school. I hope to be a source for peoples’ professional growth.”

Chris Wood
Chris Wood is originally from San Francisco. He attended the University of California-Berkeley and received his Bachelor’s in Architecture. In 2004, Chris and his family moved to Chicago’s Western suburbs, where Chris is a licensed Illinois Architect. Before joining Tandem, he served as Project Architect for a large Chicago-based firm, as well as Component Design Manager for a national home builder. Chris was brought onto the Tandem team in 2014 and currently is working as Project Architect.

Peter Szczelina
Born and raised in Park Ridge, Peter attended the University of Illinois (Champaign/Urbana) for a Bachelor of Science in Architectural Studies, and Clemson University for a Masters of Architecture & City Planning.
Peter joined Tandem in October of 2020 as Project Architect/Manager. Prior to Tandem, he worked at FitzGerald Associates Architects where he started as a Staff Architect and worked his way up to Managing Associate. Before that, he worked at ARCO/Murray Design/Build as In-House Design Architect, Urban Design Associates as Urban Designer, and CCY (Cottle Carr Yaw) Architects as a Staff Architect/Designer.
His specialties include melding a keen sense of design with a knowledge of construction when working on mid to high-rise mixed-use/multi-family/residential projects in both urban and suburban contexts. He also has experience working on several rehabs of existing buildings into corporate offices, event spaces, and restaurant/retail experiences.
Peter brings a collaborative and holistic approach to designing a building and/or its neighborhood context. His continuing interest is to incorporate innovative “Sustainable Design” concepts, materials, and technologies into the buildings and communities he helps envision. His favorite part of the job is taking a blank canvas and creating an exciting environment that encourages people to be engaged, inspired, and enthusiastic about the community they live, work, and play in.
He lives on the northwest side of Chicago with his wife, Stacy and their dog, Lulu, in a single family home that they’ve renovated and done extensive landscape work on. When he’s not designing, Peter’s enjoying the outdoors either on a hike, bike, skis, or at the dog park with Lulu. He and his wife also enjoy traveling in and out of the country to experience the life, architecture, and vitality of other cultures.

Taylor Schaub, AIAS, Assoc. A.I.A
Taylor was born and raised in the west suburbs of Chicago, but currently lives in downtown Chicago. She graduated from the Illinois Institute of Technology with a Bachelor of Architecture degree and Business minor. Currently, she is involved in several organizations, including volunteering as a Climate Action Ambassador for the Illinois Green Alliance. Her work at Tandem focuses on crafting construction documents, permit applications, presentation materials, and also performs site supervision on an as-needed basis. Taylor’s favorite part about working at Tandem is continuously accelerating her education by learning through others. She is grateful for the opportunities and responsibilities she has been handed while being a part of the Tandem team.

Kaitlyn O’Callaghan
Kaitlyn was born and raised on the Northwest side of Chicago, where she currently resides. She lived in Columbus, Ohio for 6 years while she attended college at The Ohio State University and also earned her paralegal certificate from Columbus State. When she’s not working, Kaitlyn is spending time with her nephew and family.

Ryne Malonzo
Born and raised on the Northwest side of Chicago (“Go Cubs Go!”), Ryne attended Chicago State University obtaining his a major in Recreation Management and a minor in Physical Education. He previously worked as a Concierge at an apartment building in the Streeterville neighborhood. Ryne describes being a Concierge with Tandem as being a “first responder,” as well as security, a source of communication to residents, potential residents, team members, couriers, vendors, and beyond. His favorite parts of the job are the Tandem team, the residents, and the building (Avenir).

Manuel Hernandez
Manuel Hernandez was born and raised in Chicago IL. He has joined Tandem this May of 2021 as the Assistant Building Engineer at Mode Logan Square. Before Tandem Manuel has worked at Steiner Industries as the production manager, safety coordinator and fire safety captain. This industry is growing and he is excited to contribute and share his knowledge, experience and energy to provide a safe, clean and well-organized building that exceeds our tenants’ expectations and draw focus to the Mode vision. When he is no working at Mode he loves running & cycling not just recreationally, but as sport. He can proudly say that he has completed two marathons, several half marathons and Century (100 mile) rides.