# LESSON 07: Section and Elevation of a Two-story House (continued)

From the architectural floor plan, the architect can derive the elevations of the building. The horizontal positions or sides (the jambs) of doors, windows, and other façade openings can be determined by the plan. The vertical positions of doors, windows, and other façade openings are determined in the case of a window, by height of the bottom of the window (sill) and by the height of the top of the window (the head). The vertical position of doors and windows are shown in the section. Windows and doors are shown in plan and section as shown below.

DRAWING: Graphic Conventions for doors and windows

Stairs
Stairs are made up of three elements: the vertical distance that you step up (or down) called the riser, and the horizontal part you step on called the tread, and the diagonal part on either side of the risers and treads that holds the stair together called the stringer. The width of the tread is always greater than the height of the riser. In general, the width of the tread and height of the riser will add up to 17 ½” to18”: typical indoor stairs have an 8” riser and 9½ tread but this can vary slightly. Monumental stairs often have a 6” riser and a 12” tread.

DRAWING: Stair

Class Schedule
Demonstration: Calculating stairs and ramps
Lab: Continue to construct the section and elevation of your house
Assignment: Complete Two-story house project; prepare for midterm