The former Mariners' Church is a fine early example of the Victorian Free Classical style of architecture in the form, space and surviving detail of the first chapel. The extensions completed in 1910 are a good and representative example of Federation Free Classical architecture, and are an ingenious solution to the difficult design problem of providing additional floor space above and around Bibb's original church without unduly compromising the original sanctuary space or the scale of the new building in the streetscape.
The exteriors, in particular the George Street facade, illustrate many of the essentials of that style. The 1910 and 1928 Chapels are finely detailed interiors, the first with an interesting Baroque quality, the second an Inter-War Mediterranean or Romanesque style. The building forms an effective streetscape component of George Street North and West Circular Quay, and occupies a key location at the confluence of Hickson Road and George Street.