BETHEL — Voters in four of the five SAD 44 towns gave the go-ahead for a $2.5 million renovation project at the Telstar Regional  Middle/High School during Tuesday’s balloting. The vote was 2,042 to 1,183.

Towns voted as follows: Andover, 177 yes, 332 no; Bethel, 999 yes, 397 no; Greenwood, 277 yes, 153 no; Newry, 144 yes, 72 no; and Woodstock, 445 yes, 229 no.

Andover, the only town voting against the question, is in the process of withdrawing from the district.

The district has accumulated about $1.2 million in a capital reserve account for the work. The remaining $1.3 million will come from a federal Quality Schools Construction bond at no interest for up to 20 years.

Superintendent David Murphy said by email on Wednesday that some of the less intrusive parts of the energy efficiency and ventilation improvements project will begin immediately. Other portions will take place during vacation weeks and during the summer.

The project is expected to be completed by the beginning of school year 2013-14.

Murphy said the entire building will have a new air-exchange system that will introduce fresh air into the building. It will replace the original system that was installed when the complex was built nearly 45 years ago.

Energy efficiencies are expected to include lighting, refrigeration, roof and other upgrades.