The Tricky Art of Replacing Windows in Historic Districts

When a co-op or condo board undertakes a window-replacement project, there are a lot of moving parts. If the building happens to be in a historic district, there are a lot of moving parts plus one: the Landmarks Preservation Commission (LPC). 

When the board at the 788-unit co-op at 5 Tudor City Place decided to replace the building’s steel-casement windows, it hired Bertolini Architectural Works to handle the master plan for the project. Bertolini selected an aluminum frame made by Skyline Windows. Since it was the first window-replacement project in the Tudor City Historic District, the (LPC) scrutinized the submission. 

“And they went so far as to request that Skyline and another manufacturer, Panorama, redesign their profiles a little bit to be more in keeping with what the commission was looking for,” says Eric Vonderhyde, a principal at Bertolini. 

Although 5 Tudor City Place needed three public hearings to get approval, public hearings are not required when a landmark building replaces an old window with a new one of the same kind and material. But because steel casements no longer comply with New York City’s energy code, Bertolini proposed the aluminum-framed windows, which meet thermal-efficiency standards. After the second public hearing, both vendors installed samples in the co-op’s mailroom, which enabled LPC preservationists, commissioners, and co-op board members to see them from the street. 

Approval of the master plan for 5 Tudor City Place allowed Bertolini to initiate similar projects in other Tudor City buildings, since a baseline for future projects was established. There are cases, however, where an existing master plan doesn’t save time for neighboring buildings in the same complex. For Tudor Tower, the 439-unit co-op at 25 Tudor City Place, it took more than two years to go from planning to installation. That was because air-conditioning units had to be installed in the windows when through-the-wall units couldn’t be accommodated, says Rebecca Zanes, general manager of PRC Management, the co-op’s property manager. 

Two additional window replacements at Tudor Tower since 2015 have been much easier. With a master plan already in place, the only filing required for subsequent offerings is a permit to proceed, which LPC tries to grant within 30 days. “As long as it’s in conjunction with the master plan, and there’s no changes to it,” Zanes says, “it’s more of a rubber stamp from [LPC] so shareholders know going in what they’re filing for and what they expect to be approved.”