Q: Should I/we be concerned with the resulting handrail height? It would be about 1 1/16″ lower with respect to the new treads. Would this violate any building codes?
A: Good question about codes. I don’t know. Codes vary from place to place. I can only guess that hand rail height is 36″, but that is a guess. If your hand rail is supported by spindles that are on the treads, it is a mute point, since this will all have to be taken apart to install new treads.