Structural engineers from Keast & Hood are a bit baffled in the belfry of historic Independence Hall in Philadelphia. As part of a planned $4.3-million renovation, triggered by leaks in the landmark’s tower, the local firm discovered that several lines of iron rods, which run vertically down the center of the tower’s 2.75-in.-thick wooden siding, have significantly deteriorated. But the team doesn’t know why the rods are there in the first place, so they don’t know if they need to be repaired or replaced.
“They don’t seem to have a structural function from what we can tell,” says Suzanne Pentz, K&H project manager. “We haven’t found another building built in the same manner.”