Duplex: Stacked


A small- to medium-sized structure that consists of two stacked dwelling units, one on top of the other, both of which face and are entered from the street.

Typical Specifications

Lot Front-loaded Rear-Loaded
Width* 55–75 feet 40–70 feet
Depth* 100–150 feet 100–150 feet
Area* 5,500–11,250 sq. ft. 4,000–10,500 sq. ft.
  0.13–0.26 acres 0.09–0.24 acres
Number of Units 2 2
Typical Unit Size 600–2,400 sq. ft. 600–2,400 sq. ft.
Net Density 8–16 du/acre 8–22 du/acre
Gross Density 7–16 du/acre 7–16 du/acre
Parking Ratio* 2–2.5 per unit 2–2.5 per unit
On-street Spaces 2–3 2–3
Off-street Spaces 1 per unit max. 1 per unit max.
Front* 10–25 feet
Side* 5–12 feet
Rear (main building)* 30–60 feet
Between Main and Accessory Buildings 10–20 feet
Building Size
Width 28–55 feet
Depth 28–60 feet
Height (to eave)* 20–24 feet
* Varies based on context

Idealized specifications take the best characteristics of this type and update them for today’s typical building standards, serving as a model for new development.

Front Loaded

Ideal Specifications

Width 45 feet
Depth 125 feet
Area 5,625 sq. ft.
  0.13 acres
Number of Units 2 units
Typical Unit Size
Net Density 15.5 du/acre
Gross Density 12.5 du/acre
Parking Ratio 2 per unit
On-street Spaces 2
Off-street Spaces 2
Front 14 feet
Side 3 feet
Rear (main building) 68 feet
Between Main and Accessory Buildings n/a
Building Size 2,016 sq. ft.
Width 24 feet
Depth 42 feet
Height (to eave) 21 feet

The following example(s) show this housing type documented as real-world examples as they exist today. NOTE: Documented examples may be not be up to today’s local building code standards. See the Idealized tab for up-to-date specifications in line with modern building standards.