Back Porch Mystery

We've spent some time trying to figure out what happened to our back porch. Now that the snow is finally almost gone (hoorah!), we have been able to investigate a bit more around the house. It looks like they added on what might be considered a mudroom to the back but all they did was enclose the back porch - and not well, so now it's all leaky and yucky. We've been toying with the idea of opening it back up to its original state but we can't seem to find any other houses nearby with an intact back porch - almost all have enclosed it as well or bumped out the back. We were thinking about going to the Bangor Historical Society archives and looking to see if we could find a photo but I have a feeling it would only be a photo of the front of it.