Construction of a rectory began for St. Joseph's Church in July of 1920 and was completed by the fall of 1921. That same year, the Catholic Women's League was also organized for the parish.
In the summer of 1923, the parishioners began constructing a church basement on what was to be the new site for the church. This basement was designed to serve as a temporary church while funds were being raised to complete the entire structure. By the end of January 1924, the basement of the church was blessed and was opened to the congregation for masses.
The year 1928 was a particularly eventful year for the church. Construction began on the completion of the building and on December 23rd, the first mass was held in the newly completed church.
On September 25, 1928, the new church bell was blessed by Bishop Scollard during a large ceremony. The bell was inscribed on one side with the names of the Bishop, Pastor and curate, as well as the date of the donation, and on the other was an inscription that read, "This bell was presented to St. Joseph's Parish, Sudbury, Ontario, by David B. Mulligan, Esq., Montreal, Canada." During the ceremony, the bell was rung for the first time by Dr. W.H. Mulligan, brother of David B. Mulligan.
Also during this year, St. Joseph's ordained its first priest in the basement of the church. Reverend J.A. Mulligan was ordained on June 28, 1928.