49 Marion St., Brookline
Scope of Work
- Phase One – Install 110 new commercial-grade doors, as well as new sill pan flashing in all apartments in a fully occupied, 10-story apartment building.
- Phase Two – Remove old railings and install new railings on all balconies.
Challenges
Avoiding tendons in the concrete slab while drilling holes to anchor the railings. Obtaining access and coordinating the replacement of railings in a fully occupied building.
Safety First
Safety in any building is crucial to address. An accident caused by deterioration of building materials can lead to serious injuries, liability and damage to the property owner’s reputation.
So when the rails on the balconies at the 10-story apartment building at 49 Marion St. in Brookline, Mass., showed signs of corrosion and deterioration, Intercontinental Real Estate Corporation knew they had to be replaced.
The railings on each of the 40 apartments were made of aluminum, but were in contact with iron anchors. Contact between the dissimilar metals contributed to their corrosion, according to Project Engineer Edward Moll, principal of Structures North Consulting Engineers, Inc.
Statewide RW first was retained to manage the replacement of 110 commercial-grade doors and then to replace the railings throughout the building, which was constructed in the 1970s. Statewide retained a subcontractor to replace the doors in 2018, then replaced the railings in the spring of 2019.
Statewide provided complete preconstruction and construction services, including coordinating and ordering all replacement railings for the balconies, providing temporary protection, removing existing railings over the height of the building, and replacing the railings in a fully occupied building.
Avoiding the Tendons
In addition to removing the existing aluminum railings, Statewide had to core the concrete slab for each balcony to remove metal sleeves. Adding to the challenge, Statewide had to drill new holes to install the rails and, while doing so, had to make certain the drill bit didn’t hit the post-tension cables embedded in the concrete slab.
“The railings being replaced were attached to a post-tensioned concrete slab,” Moll explained, “and it was absolutely critical that the tendons in the slab not be cut when drilling for the railing attachment.”
To protect the tendons, Statewide had the slab scanned with a metal detector and marked areas that were safe to drill. The new anchor plates they installed had slotted holes to adjust their location, so Statewide could install the railings in place without damaging the tendons. Finally, a pilot hole was drilled in the proposed location to confirm that no tendons were present.
Staging the job was difficult, Moll said, because the new aluminum alloy railings were delivered on a flatbed, and had to be offloaded and lifted up as high as 10 stories. Each railing weighed several hundred pounds.
A staging area was established to enable workers to install railings in place and the work was performed in drops. The staging provided access to the balconies from outside the building, but to keep residents safe, Statewide also blocked access to the balconies from the inside while railings were being removed and replaced.
Making Adjustments
“This was a difficult project in terms of access and in terms of coordinating a vast number of replacement railings,” Moll said. “There were also some challenges with the railings delivered and a few adjustments had to be made to accommodate existing conditions.”
There were discrepancies in some sections of the new railings, but Statewide was able to make adjustments, just as it had when working around tendons in the slab.
All railings were installed over 10 to 12 weeks at a total cost of about $1.4 million.
“Anytime a project is completed on time and on budget, it’s a good thing, but the quality of the work is of primary importance,” Property Manager Shana Foynes said. “Statewide delivered there as well, providing quality work, on time and on budget.”
