On this week’s episode of everyone’s favorite home improvement podcast, we start by issuing a small correction about plaster-of-paris. In “Mailboxes And So On,” we answer listener questions about leaky rooves, when you should replace smoke detectors, and what to do about ghosts in the attic. Finally, a quick stop in everyone’s favorite segment, “Hardware We’re Hard For” (are we really sticking with that?), takes us across the pond.