The inventory identifies two typologies: architectural massing and floor plan. Massing typology is based on the essential three-dimensional impression of a building. Often urban in scale and impact, the type reflects the general built form.
A building’s massing is often a reflection of a combination of factors such as site location, use, structure, topography, architectural style, floor plan and history of expansion or redevelopment. Massing is the iconic form and volume of the building, the profile against the skyline and core structure of a building. Massing typology is assigned based on current condition and physical evidence. A building might be built in several phases and thus evolve through a number of phases (e.g., a simple meeting hall built as a rectangular hall with gable. Subsequent additions could add a central tower on the front façade and become a central tower. Further additions such as a narthex on the front porch and a single transept and side hall might further convert the overall massing to irregular/asymmetrical.
Floor plans also have typologies and the sites identified in the Ontario’s Places of Worship inventory have been categorized according to common religious architectural plan types – some of which are thousands of years old. Plan typology involves an analysis of circulation patterns, structure and proportions. Like massing typologies, floor plan typologies are distillations of basic organizational principles and architectural strategies. Nonetheless some buildings defy such analysis and are combinations of type or, on occasion, are highly idiosyncratic or irregular.
Typologies provide a means of analyzing like architectural conditions, strategies and designs in two (i.e., floor plan) and three (i.e., massing) dimensions. They are a way to identify formal comparables and well as a means of determining how a building might efficiently be reused for a purpose for which it was not built. For instance, an amphitheatre floor plan in a Methodist church is surprisingly similar to a performing arts venue in its site lines, size and acoustics.