The Newtown Legislative Council has gotten an update on a potential redevelopment project at the Fairfield Hills Campus. The Connecticut Office of Historic Preservation responded to Newtown's plans for two empty buildings by calling on the town to preserve vacant former hospital buildings for at least five years after the completion of the redevelopment.  The town was seeking the state's backing as it gets ready to apply for historic preservation tax credits from the National Park Service.  Boston-based WinnDevelopment is looking to convert Kent House and Shelton House, built in 1940 and 1933 respectively, into housing and shops.  Kent is 200,00 square feet while Shelton is 100,000 square feet.  The estimated renovation cost is $71 million, but that was done close to a year ago.  Newtown has demolished other unsafe structures and officials have previously said the remaining buildings are dilapidated and need to be demolished as well.  First Selectman Dan Rosenthal says they're not lobbying for the entire campus to be put into historic preservation, but rather a modified district.  The state wants all of the buildings preserved.  Rosenthal says his impression was that the agencies would be more flexible than they are.  He says with layers and layers of beauracracy, he was tempted to say they would just tear down all of the buildings and do no preservation.  Whatever is done, will outlast current elected officials.  For 5 years after project completion, they can't be demolished.  If the town does go down this road, if the credits are awarded, that wouldn't happen until 2023.  The credits would flow over three years, about the length of time for construction.  With construction completed in 2027, it would be 5 years before the town could touch a building.