Which of the following describes a condition that mandates architect involvement in building projects?

The condition that mandates architect involvement in building projects is related to the complexity and scale of the project, as well as regulatory requirements established by provincial or territorial laws. In many jurisdictions, residential buildings with multiple units require the oversight and expertise of a licensed architect to ensure compliance with safety, functionality, and design standards. This is particularly important when these buildings involve shared common areas, various unit configurations, and must meet the local building code regulations that often necessitate architectural input.

In contrast, while building height and historical considerations may also require architectural involvement, those factors can vary significantly based on local regulations. For example, a building over five stories might not always require an architect if permitted by local laws for certain types of low-risk designs. Similarly, buildings with professional offices may not inherently mandate architect involvement depending on their scale and complexity. For historical renovation projects, while architects typically play a vital role, this is largely driven by the specifics of the project and local preservation laws, which may not always apply universally to all similar projects. Therefore, the requirement in option B stands out as a clearer and more standardized mandate in many jurisdictions.