By Josephine Tannuzzo ’18
On Thursday Sept. 29, Trinity College released an update and report conducted by Cirrus Structural Engineering regarding the collapse of the 1713-1715 Broad Street balcony. This report can be accessed through Trinity’s website. President Joanne Berger-Sweeney and Dean Joseph DiChristina also held a teleconference answering press questions.
According to the report, the decks were originally constructed in 1925 and had been reconstructed at some point between 1990 and 2003. The exact date of reconstruction and the company responsible for the reconstruction is unknown. The reconstruction used pressure preservative treated lumber, while certain portions of the original structure remained.
The reconstructed decks did not incorporate “best practice” construction methods, including flashing above the ledger, post base and cap hardware, lag screws fastening ledgers to the main walls, among other standard practices. The second floor deck had been rebuilt entirely, with the exception of the original ledger along the wall of the house onto which the new ledger was mounted.
The new ledger was mounted to the original ledger with two nails per stud, but the new nails were unable to penetrate the original ledger to the studs. Therefore, the original nails were relied upon for support. Since there was no flashing over the ledger, the fasteners deteriorated and corroded over time resulting in a reduction of load-bearing capacity.
The third floor deck was rebuilt on the original 1925 frame. The south beam of the third floor deck had visible deterioration and the bearing was supported by a one-inch nominal exterior sheathing of the main house. This connection was inadequate for supporting the live loads or restraining against lateral movement. Thus, when the capacity of the second deck was overwhelmed by the occupants on Sept. 10, the upward and lateral movements transferred to the third floor deck and caused a collapse, leading to the subsequent second floor deck collapse.
Trinity purchased the house in 2011, however, there are no records of any inspection taking place. Going forward, Trinity College will ensure that all of its 35 off-campus properties will be inspected by experts for safety. Trinity is still determining what will be done with the house at 1713-1715 Broad Street. In the meantime, the five students who lived in the house are currently living on campus. All of the injured students have returned to campus and classes at this time.
By Josephine Tannuzzo ’18