In 1918, members of the United Church met to discuss the possibility of church services being conducted in the mornings and evenings. For this purpose, a resident minister would be required and after some deliberation and examination of available funds, it was determined that a resident, full-time minister could be hired. By December, Reverend Edgar Frank from Waterloo, Ontario arrived to fill the position.
During Reverend Frank's tenure, a new church building was created on Young Street (where the church still stands today). Three lots were purchased for the construction and on October 3, 1920, The United Church of Capreol was completed and the opening celebration was hosted by Revered J.D. Byrnes, the District Superintendent of the Presbyterian Church in North Bay.
The original church was built in two sections. The first section was the church proper, containing a raised platform for the choir and the pulpit. The church organ was located just below the pulpit and was screened off from the view of the congregation. The seating consisted of folding chairs that were placed in rows for the service and would be rearranged by the church caretaker and his sons for Sunday School in the afternoon and then again for evening services.
Upon entering the church, the initial area was a vestibule with doors leading left to the Sanctuary and right to the church clubroom (used for various social functions). Several small rooms were built above the clubroom to be used as living quarters for the minister, however, it was soon discovered that these rooms were not ideal for this purpose.
In May of 1923, Reverend J.M. Allen was appointed as minister to the congregation and during his tenure, he arranged for the purchase of a manse on Ford Street.
On June 25, 1925, Presbyterians and Methodists joined together to become the United Church of Canada. Capreol's United Church was in favour of the national union and the name of their church changed to Trinity United Church.