Triplex: Stacked


A small-to-medium (3 to 3.5-story) sized detached structure that consists of 3 dwelling units typically stacked on top of each other on consecutive floors, with one entry for the ground floor unit and a shared entry for the units above. This type does not include a rear yard.

Typical Specifications

Lot Front-loaded Alley-Loaded
Width* 40–65 feet 40–55 feet
Depth* 100–150 feet 85–150 feet
Area* 4,000–9,750 sq. ft. 3,400–8,250 sq. ft.
  0.092–0.22 acres 0.078–0.19 acres
Number of Units 3 3
Typical Unit Size 700–1,600 sq. ft. 700–1,600 sq. ft.
Net Density 13–32 du/acre 15–38 du/acre
Gross Density 11–30 du/acre 13–35 du/acre
Parking Ratio* 1–2 per unit 1–2 per unit
On-street Spaces 1–2 1–2
Off-street Spaces 1 per unit max. 1 per unit max.
Front* 10–25 feet
Side* 5–12 feet
Rear (main building)* 5-30 feet
Between Main and Accessory Buildings 10–20 feet
Building Size
Width 24–40 feet
Depth 40–55 feet
Height (to eave)* 30–45 feet
Floors 3-3.5 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 40 feet
Depth 105 feet
Area 4,200 sq. ft.
  0.096 acres
Number of Units 3 units
Typical Unit Size 1,008 sq. ft
Net Density 31 du/acre
Gross Density 23 du/acre
Parking Ratio 1.67 per unit
On-street Spaces 2
Off-street Spaces 3
Front 15 feet
Side 5 feet
Width 24 feet
Depth 42 feet
Height (to eave) 30 feet
Floors 3 stories