Walter J. Rossiter, F–IIBEC, a longtime IIBEC member and an important advocate for the building enclosure industry, died November 10, 2025.
Rossiter joined IIBEC in 1994. During his more than three decades with the organization, he served on the IIBEC Technical Advisory Committee, Building Enclosure Symposium Committee, Advocacy Committee, and IIBEC Interface Editorial Board. He also was a member of IIBEC’s Jury of Fellows and of the Foundation Board of Directors. He attended numerous IIBEC conventions over the years and was a speaker at IIBEC events. In retirement, Rossiter served as a part-time technical advisor to IIBEC until 2024.
Rossiter’s death spurred warm remembrances from his industry colleagues.
Lyle Hogan, F–IIBEC, RRC, PE, former editor of IIBEC Interface and author of Roof Decks A to Z, described “a big void in my soul now” upon receiving the news of Rossiter’s death. “I often sought his advice in the work I tried to put forward—and he corrected me more than once,” Hogan shared. “He was a perfectionist, for sure. A scholar, without a doubt. And a mentor to any who would inquire of him.”
In addition to his many roles with IIBEC, Rossiter had been an ASTM member since 1975, serving as chair of its D08 Awards Subcommittee from 2004 through 2022. He won numerous ASTM awards, beginning as far back as 1994.
Rossiter also spent more than 35 years as a research chemist at the National Institute of Standards and Technology (NIST), where, according to a published obituary, “he worked with distinction until he retired in 2006.” Rossiter’s expertise “centered on the performance of roofing materials and systems, building materials, thermal insulations, and the in-situ analysis of lead in paint and dust,” the obituary states.
Helene Hardy Pierce, F–IIBEC, called Rossiter “a mentor to so many and one of the true statesmen of our industry” and remembered their time serving together for ASTM.
“In his many contributions, the one that stands out is his unwavering belief in acknowledging the contributions of individual members,” she said. “For many years, Walt chaired the ASTM D08 Awards subcommittee and advocated on behalf of so many. He personally wrote many, many award nominations, taking countless hours of his personal time gathering information and drafting incomparable accounts of volunteers’ contributions. Very, very few know of how dedicated he was to promoting, behind the scenes, so many ASTM members. It was a quiet role that he mastered. Walt will be missed, not least of all for his selfless service that benefited so many.”
David Hawn, F-IIBEC, RRC, CEM, and chair of the RCI-IIBEC Foundation, was stirred as he recalled the words of Albert Pike, who once said, “What we have done for ourselves alone dies with us. What we have done for others, and the world, remains and is immortal.” Hawn recalled how Rossiter embodied that idea. “The good works of our friend Walt Rossiter will live on and always remind us of the wonderful mind and caring heart that he had,” Hawn said. “I will miss Walt and especially the thorough review and information that he always provided cheerfully and with confidence. His participation and contribution to the RCI- IIBEC Foundation Board over many years will continue to be a standard for us to measure the value of anything put before us. I have to say one final thank you, even though, in the future, I will still be thanking Walt for his generous guidance.”
Dr. Ralph M. Paroli, CChem, chair of the RCI Foundation Canada, said, “Walt’s legacy is not only technical but deeply personal. He was a generous mentor, a thoughtful collaborator, and a steadfast friend to many in the roofing and building enclosure/envelope community. His wisdom, guidance, humor, and unwavering professionalism will always be remembered by all of us who had the privilege to work with him.”
“Walt was one of the first people I reached out to when I became the executive vice president and CEO of IIBEC back in 2019,” remembered Brian Pallasch, who continues in that role for the organization. “He was not only a dedicated volunteer for IIBEC starting in the 1990s, but for many years he was a part-time member of the staff team. He loved his IIBEC family and supported the organization’s mission. His dedication, compassion, contributions, and kindness touched many and will be long remembered.”
According to a published obituary, Rossiter is survived by his wife of 61 years, Marie; his children, Paul Rossiter and wife Jenny Rossiter, and Anne Rossiter; grandchildren Nick, Ben, and Ella; and siblings Robert Rossiter and Elaine Keeley.
A celebration of Walt’s life will be held at St. Paul’s Catholic Church, in Damascus, Maryland, on November 21, 2025, with visitation at 10:00 a.m., followed by a mass at 11:00 a.m. A reception will follow at Whiskey Creek Golf Club.
In lieu of flowers, the family requests that donations be made to any of the following: Boston College High School, Children’s National Hospital Foundation E11ASTRONG, Dana Faber Cancer Institute, or RCI-IIBEC Foundation Scholarship.
