WEYMOUTH — It was standing-room only in what parishioners at Sacred Heart Parish call their “churchatorium” on Sept. 8. The auditorium at Sacred Heart School has been the parish’s site for worship since June 9, 2005 when the 134-year-old church was decimated in a seven-alarm fire.

On Sept. 8, the feast of the Birth of the Virgin Mary, the community gathered for the school’s opening Mass, followed by a groundbreaking ceremony at the site of Sacred Heart’s new church building. Construction is scheduled to begin within the next two weeks and be completed at the end of November 2007.

“Our gorgeous, new church is just 14 months away,” pastor Father Daniel J. Riley said. “We’re thrilled.”

The Mass began with a student choir singing the entrance hymn.

Cardinal Seán P. O’Malley said in the homily that he was glad to celebrate the feast day and “mark a very important moment” for the parish.

Cardinal O’Malley urged parishioners to say “yes” to God, just as Mary did at the Annunciation. That “yes” was the first word from Mary in the Gospel, and her last words recorded in the Scriptures was at the wedding of Cana when she said, “Do whatever He tells you,” he said.

“So the first word from Mary is ‘yes,’ and her last word is telling us to say ‘yes’ to God, too,” he added. “Sometimes God calls us to change our plans, but every time we say ‘yes’ to God, something wonderful happens.”

After the homily, parishioners recited Sacred Heart’s building prayer.

“You give us grace upon grace to build the temple of Your Holy Spirit, creating its beauty from the holiness of our lives. As we build the new Sacred Heart Church, send Your Holy Spirit upon us,” they prayed. “We entrust our new church to the loving heart of Your son, Jesus.”

At the conclusion of the Mass, Father Riley thanked the cardinal for his constant support.

“After the church burnt down, the very first person to call us and offer sympathy was Cardinal Seán. A couple of days later he was here to celebrate Mass at our ‘churchatorium,’ and about three days later the cardinal gave us his blessing to build our new church,” he said. “As the cardinal said, if Mary hadn’t said yes, Jesus wouldn’t have been born. But if the cardinal had not said yes, our new church wouldn’t be born.”

Cardinal O’Malley and Father Riley processed out of the school auditorium first, followed by students who had donned yellow hard hats. The cardinal gave a blessing before the groundbreaking.

“Bless all those who are working to provide this site on which a church will be built. Today may they rejoice in work just begun. Soon may they celebrate the sacraments in Your temple,” he said.

Then he and school children representing different grades picked up shovels adorned with red and white ribbons and dug into the mound of dirt at the site.

Insurance will pay to replace the building that the State Fire Marshall’s Office determined was destroyed by fire from a malfunctioning refrigerator in the basement of the church.

Very few items survived the flames, but firefighters were able to salvage the tabernacle and its contents. Several of the Stations of the Cross, two bronze plaques with the names of parishioners who served in both World Wars, two marble holy water fonts, and a few statues were also retrieved.

It took over a year to clear the rubble, design the new church and prepare for construction. It will take about the same amount of time to rebuild, according to Robert Cassidy, assistant director of Facilities Management for the archdiocese.

The facilities office completes $20 to $40 million of work each year on parish centers, renovations or expansions. The most recent major project was a renovation at St. Patrick Parish in Stoneham, which was completed last year. But the new parish at Sacred Heart is a much larger project, he said.

“This is probably the largest contract we’ve undertaken in a long time,” he added.

Kerry Dunn, a parishioner who has two daughters enrolled in the school, said she is excited about the new construction.

“I’m glad that they got to rebuild the church. The people here are really great; they deserve it,” she said.

Dunn said she and her family were in Vermont when the fire broke out.

“By the time we got here, it was completely demolished,” she said. “We were devastated.”

Lois Bisson grew up in the parish, attended the high school before it closed and taught there for a year after college. She and her husband, Al, married at the church. They also watched the building burn down.

“I’m just so thrilled that the church is coming back,” said Lois. “My roots are here.”

Father Riley also mentioned that the lack of a church building has not negatively affected the school.

“The church is not even built and yet the school enrollment is up by 25,” he said. “The enrollment was great last year, and it’s terrific this year.”

The school now has 306 students who will have the opportunity to learn from the construction of the new church, according to principal Mary Reardon Ferrucci.

The school’s theme this year is “Let us build the city of God,” and the principal already has plans to bring electricians and bricklayers into the school to explain the construction to students.

“We’re really embracing it,” she said. “We’re really hoping to incorporate this historical event with our daily school.”

Caroline Cameron, a seventh-grader, and her brother, Johnny, a fifth-grader, have attended school at Sacred Heart since preschool. They both say they miss the old church but are ready to see it rebuilt.

“It’s nice that they’re gonna build it,” Caroline said. “I think it’s cool that we get to see how they do it and watch from school every day.”

Johnny, who held one of the shovels during the groundbreaking, added “I’m really excited.”