The original building was unfortunately gutted by a fire in March 1922 leaving only the outer walls. Architect Louis Parant was commissioned for the reconstruction who decided to build an entirely new building which included a remodelling of the Mansard roof into a new Beaux-Arts inspired model. The new building opened in 1926

https://en.wikipedia.org/wiki/Montreal_City_Hall