Published: 26.02.25
DBI and door manufacturer Jeld-Wen are analyzing and documenting the fire resistance of reused fire doors through the ReDoor project. They are also developing documentation methods and possibilities for certification. Initial fire tests show that both old doors and artificially worn doors perform convincingly.
The ReDoor project is highly relevant, as new selective demolition regulations took effect on July 1, 2024. These regulations aim to promote the reuse of building materials and ensure a more structured approach to construction waste management.
“Old fire doors are among the building materials with the potential for reuse. However, under current fire safety regulations, a used fire door cannot be installed in a new building due to a lack of documentation. This is unfortunate at a time when there is a strong focus on circularity and reducing resource consumption. That is why the ReDoor project is examining all the necessary aspects to make it possible,” says Hauke Thiessen, Sales Director at Jeld-Wen.
Jeld-Wen, the world’s largest manufacturer of doors and windows, has partnered with DBI to analyze and document the fire resistance of reused and artificially worn doors compared to brand-new ones. At the same time, the project aims to create relevant documentation methods and certification opportunities for reused fire doors.
Practically, the idea is that Jeld-Wen employees will visually screen fire doors from buildings scheduled for demolition. Suitable doors will then be sent to Jeld-Wen’s factory for refurbishment, which may include painting, installing new hinges, and upgrading lock cases. Once refurbished, the doors should be ready for installation in new buildings as if they were brand new. This process must be systematic, scalable, and subject to third-party oversight.
The road ahead is still long, but the first important steps have been taken. Fire tests have been conducted on an old fire door and several artificially worn doors to determine whether they still meet the BD30 fire classification.
The tests were based on a 15-year-old fire door from a hospital. Jeld-Wen created copies of the door and subjected them to artificial wear. Some doors underwent a ‘soft body impact test,’ where a 50 kg object was swung into the door’s center to stress both the door leaf and hinges. Others were subjected to a ‘hard body impact test’ with localized impacts, while some underwent a cyclic test, where they were opened and closed 200,000 times.
"The goal was to understand, under controlled conditions, how wear affects the fire resistance of fire doors. We wanted to see if doors retain their properties after many years, and whether this can be demonstrated,” explains Trine Dalsgaard Jensen, an Engineer in DBI’s fire testing department.
"This system, which will be available to all fire door manufacturers, must not only apply to doors already in use but also to doors produced today that will be reused in the future. Simulating wear and aging is crucial in determining whether a door can be reused in 15 years," adds Asmus Haastrup, an Innovation Consultant at DBI.
Subsequent fire tests conducted in DBI’s and Jeld-Wen’s test laboratories delivered impressive results. The 15-year-old hospital fire door was tested alongside a brand-new, unworn door and had no trouble meeting the BD30 classification – the same rating it had when originally produced and installed.
“There was no loss of performance compared to a new door. The old fire door, which was in good condition, performed very well,” says Trine Dalsgaard Jensen.
The artificially worn fire doors also performed successfully.
“The damage from the hard body impact test – similar to the surface scratches that doors acquire over time from carts and cleaning equipment – had no effect. Even more interestingly, while the door’s core material was weakened by the 50 kg impact in the soft body impact test, this did not directly affect fire resistance. However, the door ended up hanging slightly askew, finishing just one minute short of the 30-minute classification,” explains Trine Dalsgaard Jensen.
“The same pattern emerged with the door subjected to the harsh cyclic test. The door itself was still in good condition, but after hundreds of thousands of openings and closings, the door leaf was misaligned. This highlights the need to adjust reused fire doors upon installation,” she adds.
DBI and Jeld-Wen are continuing their work on the project.
"We have successfully used fire doors to test a method and define the framework for further work. We are building on existing standards and adding elements of wear and aging to document that reused fire doors still meet fire safety requirements. The test results will help determine the appropriate qualification test requirements. For example, we do not yet know if 200,000 open-close cycles are the correct benchmark or if fewer would suffice. At the same time, we are in dialogue with DNV to develop a certification scheme," says Asmus Haastrup.
DBI and door manufacturer Jeld-Wen aim to enable the reuse of fire doors without compromising safety. The ReDoor project analyzes and documents the fire resistance of reused and artificially worn doors compared to brand-new doors. It also develops documentation methods and certification possibilities for reused fire doors.
The project started in September 2024 and is funded by Jeld-Wen and the Danish Ministry of Higher Education and Science through DBI’s performance contract.
