Series consists of textual records outlining the general criteria used by Gordon Couling for his architectural inventory of buildings built in Guelph prior to 1927. Couling's criteria consisted of five different sets of priorities numbered one through five, each accompanied by brief explanations for its use. Based on his criteria a building was then given a priority number. In addition, Couling sometimes included additional notes about a particular building's history and architectural features.

Couling's general criteria is explained at the beginning of the series followed by the priority sheets which are arranged alphabetically by street name.

Series consists of textual records with corresponding photographs for buildings built on Preston Street before 1927. Information about the location, architect, contractor, original owner, original use, construction dates, and the building materials used in construction may be identified.

Buildings are arranged sequentially with odd numbered buildings listed first.

Series consists of textual records with corresponding photographs for buildings built on Powell Street West before 1927. Information about the location, architect, contractor, original owner, original use, construction dates, and the building materials used in construction may be identified.

Buildings are arranged sequentially with odd numbered buildings listed first.

Series consists of textual records with corresponding photographs for buildings built on Powell Street East before 1927. Information about the location, architect, contractor, original owner, original use, construction dates, and the building materials used in construction may be identified.

Buildings are arranged sequentially with even numbered buildings listed first.

Series consists of textual records with corresponding photographs for buildings built on Pipe Street before 1927. Information about the location, architect, contractor, original owner, original use, construction dates, and the building materials used in construction may be identified.

Buildings are arranged sequentially with even numbered buildings listed first.

Series consists of textual records with corresponding photographs for buildings built on Petrolia Street before 1927. Information about the location, architect, contractor, original owner, original use, construction dates, and the building materials used in construction may be identified.

Series consists of textual records with corresponding photographs for buildings built on Pearl Street before 1927. Information about the location, architect, contractor, original owner, original use, construction dates, and the building materials used in construction may be identified.

Buildings are arranged sequentially with even numbered buildings listed first.

Series consists of textual records with corresponding photographs for buildings built on Park Avenue before 1927. Information about the location, architect, contractor, original owner, original use, construction dates, and the building materials used in construction may be identified.

Buildings are arranged sequentially with even numbered buildings listed first.

Series consists of textual records with corresponding photographs for buildings built on Palmer Street before 1927. Information about the location, architect, contractor, original owner, original use, construction dates, and the building materials used in construction may be identified.

Buildings are arranged sequentially with odd numbered buildings listed first.

Series consists of textual records with corresponding photographs for buildings built on Paisley Street before 1927. Information about the location, architect, contractor, original owner, original use, construction dates, and the building materials used in construction may be identified.

Buildings are arranged sequentially with odd numbered buildings listed first.