The Winthrop Center is officially certified by the Passive House Institute (PHI) as the largest passive house office building in the world

Fri 20/10/2023 - 06:01

We are excited to announce that the Winthrop Center is now officially certified by the Passive House Institute (PHI) as the largest passive house office building in the world!  
Following an impressive six-year journey of conceptualization and construction, the visionary project by 
MP Boston and Handel Architects was inaugurated in Boston this spring. The mixed-use tower encompasses 812,000 square feet of Class A office space, alongside an additional 510,000 square feet hosting 317 luxury residences. 
The office spaces within the Center are designed to incorporate between 30 to 35% more fresh air compared to conventional commercial designs.  

SOCOTEC takes immense pride in having played a pivotal role, offering our expertise in Exterior Wall, Roofing, and Waterproofing Consulting & Monitoring services for this remarkable project.  
This project is a testament to the power of collaborative innovation in the realm of sustainable architecture, specifically for large scale buildings. We're excited to see how the Winthrop Center will serve as a beacon of inspiration for future implementations of the Passive House method in Boston and worldwide! 

Jennifer Sze, Principal with SOCOTEC, shares, "Working on this record-breaking tower from design through to completion - and now certification - has been rewarding. The triple glazed and super airtight curtain wall system played an important role in achieving Passive House certification. Our team at SOCOTEC worked closely with Handel Architects to develop design details thoughtfully rooted in practicality and constructability specific to high rise building, minimizing issues during the building's construction."

“With Winthrop Center, we wanted to think beyond the status quo, and we were ready to employ an innovative approach in order to deliver an unparalleled experience and quality of life. With this official certification by Passive House Institute, we are introducing a new era in building design that prioritizes the environment, human comfort, and health. Through collaboration with partners like SOCOTEC, creativity, hard work, and dedication, we’ve brought the most energy efficient solution for large scale buildings to the heart of Boston, and we can’t wait to see more successful implementations of the Passive House method across the globe.” - Millennium Partners Founder, Christopher M. Jeffries.

A special ‘Thank You’ to all the companies and professionals that collaborated to make this project recognition a possibility!

SOCOTEC Team Members included:

  • Jennifer Sze
  • Christophori Dowd
  • Leonardo Toro
  • Esteban Mercado Molina
  • Angelo Sierra
  • Kanjin Zou
  • Alex Barmas
  • Joelle Nelson
  • Jeffrey Somerlot
  • Alberto Franceschet


SOCOTEC, who employs over 450 professionals in more than 20 offices in the U.S., is an industry leader in the building and infrastructure sectors, offering the combined highly technical expertise of an expansive and holistic network of experts across six service lines: (i) Building Envelope; (ii) Energy & Sustainability; (iii) Code & Planning; (iv) Project Advisory; (v) Dispute Resolution; and (vi) Specialty Engineering.

SOCOTEC Group, a leader in construction inspection and a major player in TIC for the construction and infrastructure sectors, the SOCOTEC Group has 200,000 clients with operations in 26 countries, 11,300 employees and over 250 external recognitions.

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