How to Read Architectural Plans for Residential & Commercial Construction

Architectural plans fully describe a building's construction. Both residential and commercial projects are 3-D structures requiring many two-dimensional drawings to document the work. These drawings include orthographic projections, isometric projections and perspectives. Orthographic projections are plans showing horizontal cuts through a structure, sections showing vertical cuts through a structure, and elevations showing the interior and exterior faces of a structure. Isometric projections are 3-D representations with accurate dimensions and perspectives are 3-D views of a building as our eye would see it. The individual drawings are referenced to one another with call out symbols. Understanding how to interpret call out symbols allows you to read architectural drawings.

Architectural drawing set

Instructions

- 1
  Locate the plan of the residential or commercial project in your set of plans. If the structure has multiple stories, there will be many plans -- find the bottom or main floor plan. The plan will be annotated with room names, dimensions, notes, as well as call out and section cut reference symbols. The call out and section cut reference symbols have a circle with a line running through the middle of it. There are two numbers on the top and bottom subdivisions of the circle, and these numbers within the circle describe the location of other drawings within the set.
- 2
  Read the reference call out circle and numbers within. The top number is the drawing number, and the bottom number is the page number. So, a reference call out circle with 2 on the top and A304 on the bottom means drawing 2 on page A304 in the architectural plans. In this way, these references work like a book's index.
- 3
  Find the page referenced by the call out circle. If there is only one page, the call out circle might not give the page number, only the drawing number. Next, find the drawing referenced. Like the plan, the referenced drawing will have annotations and other drawings referred to in the set.

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Architecture