New Canaan Police on Monday walked through the Elm Street office building that’s the town’s highest elected official has said could serve as a future department headquarters, and the Board of Education is slated to do its own walkthrough there during the first week of September, officials said Tuesday. First Selectman Kevin Moynihan has developed and championed the idea of New Canaan purchasing the 28,000-square-foot “Covia” building at the corner of Elm and Grove Streets as a future home for both the police and school district’s administrative offices—a move that would be financially feasible, he has said, if the current NCPD building on South Avenue could be sold to a developer who would preserve the historic structure, possibly for conversion to senior housing. “We are going to evaluate,” Moynihan said of the town’s hard look at the Covia building during a regular meeting of the Board fo Selectmen. “Assuming the conclusion is it works for the police and that the Board fo Ed believes it works for them, we would then during September do the financial analysis as to whether we want to recommend that choice as opposed to renovating [the current police headquarters],” Moynihan said at the meeting, held in Town Hall. “A lot of that will depend on what we can do with the South Avenue building, because the net cost would be substantially less than renovating the police building for that purpose.