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ABOUT KEG
Big-city facade experience. Independent-firm attention.
Kosco Engineering Group, PLLC was founded by Aaron Kostrzewa, PE, who left the corporate sector to pursue a vision of engineering excellence independently. Aaron’s background is in unitized curtainwall for high-rise and avant-garde buildings in San Francisco, Boston, New York, and beyond — experience he now brings to clients of every size.
In a construction industry often hampered by delays and unresponsive stakeholders, KEG distinguishes itself by prioritizing timely communication and clear, concise engineering explanations tailored to each discussion. We work closely with owners to devise solutions that go beyond mere safety — ensuring structural integrity and innovation in every project.
Aaron J. Kostrzewa, PE
Managing Member — BS Civil Engineering, Michigan Technological University
TRACK RECORD
Selected scopes led by Aaron
178,168 SF
Unitized curtainwall, lobby walls, wood & terracotta rainscreens, canopies, and railings — lead engineer for the unitized curtainwall scope.
101,700 SF
Unitized curtainwall including fly-by structure, closed cavity facade, soffits, and column cladding — lead engineer.
61 stories
Mixed-use skyscraper in downtown San Francisco — unitized curtainwall and stainless steel panels.
37,300 SF
Unitized curtainwall and storefronts — engineer of record and lead engineer.
LICENSURE
Licensed where you build
Aaron is a licensed professional engineer in six states, with licensure in additional states available on request.
DE
Delaware
MA
Massachusetts
ME
Maine
MI
Michigan
NY
New York
OH
Ohio
MISSION
To be a trusted partner delivering exceptional engineering solutions through innovative design, meticulous attention to detail, and unwavering commitment to our clients — combining technical expertise with a client-focused approach.
VISION
To be a respected and reliable engineering firm known for high-quality solutions and strong client relationships, built through personalized service and attention to detail.
INSURANCE
Professional liability, general liability, and umbrella coverage. Certificates of insurance available on request.
ENTITY
Kosco Engineering Group, PLLC — a professional limited liability company registered in Michigan.
STANDARDS
Work performed to applicable codes and reference standards — IBC, ASCE 7, ADM, AISC, ASTM — cited in every deliverable.
Talk to an engineer.
Direct access to the PE doing the work — no layers in between.
Validate your world with KEG. Licensed professional engineering in DE, MA, ME, MI, NY, and OH.
© 2026 Kosco Engineering Group, PLLC
Structural · Facade · Inspections · Envelope Consulting