The former Immaculéé-Conception Church is of considerable heritage interest for its architectural value. It illustrates the constantly evolving expertise of the Oblate missionaries. Designed and supervised not by an architect, but by Brother Léopold Ouimet, one of the order's most influential master builders, it stands out for its sober, modern, and well-executed architecture.
Built on concrete foundations and a slab supporting walls and a steel frame, the church features clean lines and a spatial layout that promotes fluidity between celebrants and worshippers. It features Ouimet's main architectural signatures: a high, luminous nave, geometric bell towers and spires set on square bases, and a choir designed to accommodate a backlit altarpiece dominated by a monumental statue of the Virgin Mary, a common feature in Oblate churches.
It is one of the most accomplished examples of Léopold Ouimet's work. Several of its features have been replicated in other churches in the region, including the one in Ville-Marie, built in 1960. Today, it remains one of the best-preserved Oblate buildings in the region.