Fourplex: Stacked


A detached (2 to 2.5 story) structure with four dwelling units, two on the ground floor and two above, with shared or individual entries from the street. This type has the appearance of a medium-sized single-unit house and may include a rear yard. This type is attractive to developers by generating four units on a typical 50’ lot.

Typical Specifications

Lot Front-loaded Alley-Loaded
Width* 60–75 feet 50–65 feet
Depth* 100–150 feet 100–150 feet
Area* 6,100–11,250 sq. ft. 5,000–9,750 sq. ft.
  0.14–0.26 acres 0.11–0.22 acres
Number of Units 4 4
Typical Unit Size 500–1,200 sq. ft. 500–1,200 sq. ft.
Net Density 15–29 du/acre 18–35 du/acre
Gross Density 13–22 du/acre 14–25 du/acre
Parking Ratio* 1-2 per unit 1-2 per unit
On-street Spaces 2–3 2–3
Off-street Spaces 1.5 per unit max. 1.5 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 36–56 feet
Depth 32–60 feet
Height (to eave)* 20–28 feet
Floors 2-2.5 stories
* 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.

Alley Loaded

Ideal Specifications

Width 50 feet
Depth 120 feet
Area 6,000 sq. ft.
  0.138 acres
Number of Units 4 units
Typical Unit Size 1,200 sq. ft
Net Density 29 du/acre
Gross Density 22 du/acre
Parking Ratio 1.5 per unit
On-street Spaces 2
Off-street Spaces 4
Front 15 feet
Side 5 feet
Width 40 feet
Depth 60 feet
Height (to eave) 21 feet
Floors 2 stories

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.