Sealed bids have been opened from firms hoping to undertake major renovations at Decas Elementary School, and all of them are significantly under budget.

Bids from three construction companies were read aloud Thursday afternoon by project manager Charles Roberts, of Colliers International, in the Multi-Service Center.

By his side were Wareham Public Schools Finance Manager Michael MacMillian and project architect Paul DiGiandomenico of ICON Architecture of Boston.

At April Town Meeting, voters approved spending up to $2.4 million for the Massachusetts State Building Authority Accelerated Repair Project at the aging school.

The money will be used to replace a leaky roof and a boiler system that is nearing 50 years old. Under the state program, the town will be reimbursed up to 70 percent of the total project cost, after it fronts the repair funds.

Bids ranged from $1,165,300 (Attleboro-based Nadeau Corporation) to $1,284,601 (East Providence-based J.J. Cardosi Inc., and $1,455,300 (Braintree-based Paul Rogan Company Inc.)

MacMillian said all the bids will be thoroughly vetted before a decision is made, likely within seven days.