What you could model, which would get you out of a hole so to speak, is have a scene with workmen blocking up one door, with just a chink of light left, scaffolding, cement mixers, and so on. Leave the other one open, which would give you a glimpse into the past, and be current at the same time. Anyone familiar with the place will know that ultimately know that they were all closed in, so you'd present your historical timeline in one fell swoop and also have a cool little diorama.