Technology Education Department
Technical Drawing Program

• An elevation is a drawing that shows the client and the contractor what the exterior of a structure looks like.
• Front, back, rightside, and leftside elevations are used to show the vertical heights of the floors, ceilings, windows, doors and ridge line; the materials used on the exterior walls, window and door trims, fascia and roof; the orientation and type of windows and doors; the amount of overhang; and the pitch of the roof.
• Elevations can be created by using an "elevation layout" that includes all of the vertical measurements: ground level, top of foundation wall, top of sill plate, finished floor, spacing of siding, top and bottom of windows, size of fascia, finished ceiling height, shingle spacing, ridge heights, and top of chimney. The "elevation layout" along with a floor plan are used to project uniform elevation views.
• Front, back, rightside, and leftside elevations are drawn or plotted at a scale of 1/4"=1'-0". The back, rightside, and leftside elevations may be plotted at a scale of 1/8"=1'-0" to conserve paper. Angled, curved or partially hidden sides must be "developed" or "rotated" as separate elevation views to show their true shape.
• Materials are shown using textured patterns, fills or hatching and labeled with a leader and appropriate lettering.
• The ground line is usually 6" below a 4" thick concrete slab floor and 16" to 18" below a wooden joist and subfloor. The ground line must be 6" below the top of the concrete foundation wall when a full basement is part of the house.
• The floor thickness depends on the size of the floor joist and the type of subfloor:
  2x10 joists @ 16"O.C. with 3/4" tongue & groove plywood measures 10"
  2 x 12 joists @ 16"O.C. with 3/4" tongue & groove plywood measures 12"
• The tops of windows should be aligned with the tops of doors either 6'-8" or 7'-0".
• Wall heights of 8'-0", 9'-0" or 10'-0" are increased by 1.5" to allow for ceiling and flooring materials:
  .5" for drywall on ceiling, .375" to .5" for ceramic or vinyl tile underlayments, .75" to 1.0" for marble or stone, .375" to .75" for hardwood flooring or .25" to 1" for padding and carpeting.
• Ceiling joists between the first and second floors are usually 2x12's with .75" T&G plywood for a total of 12" of thickness.
• Rafters are usually 2x6's, 2x8's or 2x10's @ 16" O.C. with .5" or .625" T&G plywood sheathing and asphalt or cedar shingles and measure 6", 8" or 10" respectively.
• The ridge line is the highest point of the roof intersections.
• A gable roof has a single ridge running the length of a building with the roof sloping in two directions.
• A hip roof has a shorter ridge with the roof sloping in four directions.
• A shed roof slopes in one direction only.
• The pitch of a roof is usually expresses as the the amount of "rise to run" in feet or inches:
  3" or 4" in 12" for warm dry climates and ranch or prairie style homes (example 3/12 pitch)
  5" to 8" in 12" for wet climates and traditional or colonial style homes (example 6/12 pitch)
  12" to 18" in 12" for snowy climates and chalet or A-frame style homes (example 12/12 pitch)
• Chimneys and furnace vents must extend 24" above the ridge of the roof if within 10'-0" of the ridge. If the chimney is over 10'-0" from the ridge, the top of the chimney must be 24" above a point 10'-0" away from the center of the chimney.
• The roof overhang is influenced by the style of the house, the climate of the building site, the height of the walls, the height of windows and doors and the slope or pitch of the roof.
• The overhang (measured at the bottom of the fascia) should not be lower than the framing at the top of windows and doors. A typical fascia is 6" to 7.25" in height and can be made from wood, vinyl or aluminum.