The expansion should be complete by mid-February, a Loeb Properties release states. Lafayette's Music Room at 2119 Madison will stay open despite the construction.
Lafayette's offers Southern food, nightly live music and indoor/outdoor bars on both the ground and second floor.
The new stage will be where the original Lafayette's stage had been.
A portion of the expansion space that had sheltered The Attic also will house Midtown Mercantile, a shop "providing a curated collection of one-of-a-kind local gifts and designs'' from Midtown institutions, the Loeb release states.