Preservation advocates are anticipating the release of the New-York Historical Society’s plans to build a residential tower on its Upper West Side property, after the Landmarks Preservation Commission yesterday backed the institution’s plans to renovate its façade.

The commission voted unanimously to approve a revised version of the historical society’s proposal to alter the exterior of its neoclassical building on Central Park West, between 76th and 77th streets. The changes now include lowering windowsills to create two additional front entrances and install two outdoor promotional kiosks, though a plan to add two handicapped-accessible ramps and widen entryways was abandoned.

Some opponents of the plan say it is guise for the historical society’s more ambitious proposal to build an addition and erect a residential tower on its property. But the society’s president and chief executive, Louise Mirrer, said the projects have never been linked. After yesterday’s vote, Ms. Mirrer said it is now up to the institution’s board to decide how to proceed with the tower proposal.

In another unanimous vote yesterday, the commission granted landmark status to the Crown Heights North section of Brooklyn. The neighborhood is home to hundreds of buildings constructed between the 1860s and the 1930s in architectural styles such as Romanesque Revival and Queen Anne.