You say the gutted area was a bedroom and small den. By gutting it you made it uninhabitable and decreased the home's value by one bedroom. From an appraisal standpoint the bedroom is worth 8-10K. While that may not seem like much, the bank views it as the difference between say a 3 bedroom house vs a 4 bedroom house. I would get the sheetrock up as soon as possible so the appraiser can count the bedroom and possibly the bath. Don't forget to get permits and a certificate of occupancy for the bath.