Jackhammering by day and tearing roads by night.
Work is scheduled to commence in the spring of 2012 and be completed in the fall of 2013, if all goes to plan.
Selectmen unanimously voted to write into a bid that a contractor must split construction work evenly between a 7 a.m. - 5 p.m. shift and a shift from 8 p.m. - 6 a.m.
"Once the project starts, it doesn't mean that for the duration of the project there is a construction crew in front of your business or your residence 8-10 hours a day, four to five days a week," said selectman Michael Butler. "There will be times when you're not going to be affected at all."
Jackhammering and other ear-shattering work must be done during the day - if possible - and tearing up roads must be done at night, selectmen said.
The goal is always keep two-way traffic during the daytime - which can see as many as 2,500 cars per hour - and minimize noise for sleeping neighbors overnight.
Businesses in Dedham Square contended daytime construction would be detrimental to their bottom lines and overwhelmingly favored overnight construction.
"At the end of the day when the project is done, it will be horrific for everybody if we've got an empty building up there," said Charles Black, of the Knights of Columbus, which manages the leases for several businesses in Dedham Square. "If it has to go 50-50, that is better than it going all during the day."
Residents of Dedham Square said vibrations could damage historic homes and they worry about pedestrian safety during the construction season.
Thirty-seven residents signed a petition asking selectmen to recommend daytime construction, said Mike Tracy, an apartment manager in Dedham.
With the 50-50 compromise, selectmen aimed to satisfy both camps and settle what selectman Paul Reynolds called a "doozy" of a decision.
"Over the last few weeks, not a day has gone by where one of us hasn't spoken to a merchant or a resident about the impact," Reynolds said. "The overall strategy is try to create a plan that gets this done in as short of period as possible. We all know there is going to be pain."
In addition to the vote on the hours, in quicker discussions selectmen decided the following:
- Allow free parking throughout the Square during construction
- To adopt the recommended parking plan that includes 71 free parking spaces in the Keystone Lot
- Allow one free 10-minute space outside the U.S. Post Office
- Designate "police business only" spaces near at the station
- An audible street-crossing signal that beeps 24 hours a day at 35 decibels - a notch above background noise.