Section

A section is made by slicing through a building with an imaginary vertical plane and drawing what you see. Whatever the plane cuts, such as floors, walls, roofs and the ground, is drawn heavier; what lies beyond is drawn in elevation behind it. The section is the drawing that explains height: ceiling heights, double-height spaces, stairs, roof build-ups and how the building sits in the terrain. Section lines are marked on the floor plan so the reader knows exactly where the cut was taken.

How it shows up in a project

• Choose the cut line carefully. A section through the stair, the atrium or the change in level tells the story; one through a row of identical rooms says little.
• Long sections and cross sections are usually drawn as a pair.
• Detailed sections at larger scales, such as 1:20 or 1:5, show wall and roof build-ups during design development.
• Section perspectives, which add a one-point perspective behind the cut, show both the construction and the experience of the space.
• Keep the ground line and the context in the drawing, since a section without the site loses half its meaning.

In Rendair

A section drawing can be rendered like any other drawing, adding materials, light and people so the spaces read as inhabited. Sketch to Render and Image to Render both accept a section as input, and Populate Render can add figures afterwards to show scale across the levels.