Renovating the old high school for re-use by Westport's municipal offices, senior center and school administration would cost just over $29 million, while renovating the town's current offices would cost about $18 million, a consultant told the Long Term Building Reuse Committee last week.

Matthew Littell of Utile Architects said last week that while the costs aren't certain, "they're pretty solid overall numbers for planning purposes" as Westport officials study what they should do about their aging municipal offices, senior center and the mostly vacant school, which currently houses only the school administration offices.

Though the cost to renovate the old school would be more than 50 percent higher than renovating current offices, the town would end up with more space for offices and services, and an additional 8,700 square feet of "overflow program spaces" would be created within the old school.

Overall, Littell said, renovating existing municipal offices and the senior center would cost roughly $520 per square foot, while transforming the old high school would cost $497.85 per square foot.

Under the study, the auditorium, cafeteria and some other unusued areas would be demolished, as "there's not enough programs to fill any of it," Littell said. "There was just too much room (so) that seemed like the most logical thing to do."

If the town moves toward decommissioning its current senior center, town hall and annex offices in favor of renovating the old school, and it is approved by voters, the school administration offices would stay "more or less" where they currently are within the school, along its south end, he said. Further:

• The new senior center space would be housed on the first floor, where the library currently is, and its allocated space would increase from its current 5,124 square feet to just over 8,000.

• Some town hall functions would be sited on the ground floor, with most on the second; overall, functions currently housed at town hall and the annex would jump from about 15,500 square feet of current space to approximately 20,000 square feet.

• Apart from dedicated spaces, some 8,700 square feet of "overflow program spaces/flexible classrooms and daycare" would be created.

• The gymnasium would remain "as a kind of community asset," and would provide the town with roughly 22,000 square feet of space.