Project Details
- Project Name
- Tiny Tower
- Location
-
PA ,United States
- Architect
- ISA
- Client/Owner
- Callahan Ward
- Project Types
- Single Family
- Project Scope
- New Construction
- Size
- 1,250 sq. feet
- Awards
- 2019 AIA Housing Awards
- Shared by
- Madeleine D'Angelo
- Project Status
- Built
- Cost
- $265,000
This article appeared in the July 2019 issue of ARCHITECT:
Brian Phillips, AIA, and Deb Katz, AIA, both principals at Philadelphia-based ISA, have dubbed the firm’s recently completed 38-foot-tall single-family residence Tiny Tower. The 1,250-square-foot structure rises from a minuscule 12-foot-by-29-foot site in the city’s Brewerytown neighborhood, and sits on a narrow thoroughfare where its neighbors are garages and off-street parking pads.
Philadelphia’s grid dates to the late 17th century and includes many of these narrow secondary arteries that are akin in scale to alleys in other cities. But here, the petite streets have a tradition of small “trinity” houses that were built primarily for working-class residents in the 18th and 19th centuries. The classic trinity is two stories, plus a basement, with a single room per floor. Tiny Tower is a trinity on steroids: “We’re doing a five-story version,” Phillips says. “But it’s very much in keeping with some of the old ways of building in the city.”
The house has six levels of living space, including its rooftop deck, and received a building permit in an almost effortless 10-day process, since the unusual structure was designed as of right to Philadelphia’s zoning codes. Two setbacks were required at the back of the property: The basement and first floor are set back 3 feet and accommodate a sunken garden; the three upper floors are set back an additional 3 feet.
Sinking the basement and first floor served several purposes: Overall building height was capped at 38 feet by zoning, so it was easier to fit the five interior floors within the available envelope by going down. The first floor is set three steps below grade, which separates the living room from the street. “And the basement kitchen is very much in the tradition of the trinity house,” Phillips adds.
The layout is straightforward, with a single room per floor: The basement has the kitchen; the entry level the living room; the second floor an office; the third floor a bedroom and bath (that can serve as a powder room for guests); the fourth floor the master suite; and the whole structure is topped by a roof deck. How each floor is used can be mixed and matched to a certain extent, depending on the needs of the occupants, as the project was designed as a speculative development.
The most difficult programmatic challenge was locating the stair, and in the end, the team decided to put it at the front of the house. “It frees up the space,” Phillips says. “Once you’re past the stair, you get a complete room” on each floor. The folded plate metal composition is tight against the front wall—and visible, via windows, to the street. Perforated metal baluster panels help distribute natural light throughout the house.
Finishes are simple and bright: Walls and ceilings are clad in white-painted gypsum board, floors are lined with light-stained wood, and windows have metal-clad wood frames. The front and back façades are covered in standing-seam metal siding, while the blind party walls—likely to be hidden by adjacent construction in the future—are clad in durable, inexpensive Hardieplank. And while the upper floors of the tower are conventionally wood framed (the basement structure is concrete), the extreme proportions required a structural flourish, which the architects exposed on the interior: a steel moment frame that helps carry the basement and first floors. “It’s like a big stiffener or a big flitch plate,” Phillips says.
Phillips notes that Tiny Tower isn’t necessarily a solution for affordable housing, since building taller does cost more. But similar houses can be “market tempering,” he says. “The difference between an 1,100-square-foot house and a 3,000-square-foot house is real, and the land cost is discounted due to its size.” Tiny Tower is an especially compelling prototype for infill housing and proof that overlooked sites can be opportunities for architectural ambition.
Project Credits
Project: Tiny Tower, Philadelphia
Client: Callahan Ward
Architect: ISA, Philadelphia . Brian Phillips, AIA, Deb Katz, AIA (principals); Alex Gauzza, AIA (studio director); Matt Underwood (designer)
Structural Engineer: Larsen & Landis Structural Engineers
M/E/P Engineer: J+M Engineering
Stair Fabricator: En-Motion Design
Size: 1,250 square feet
Cost: $265,000
Project Description
This project won an award from the 2019 AIA Housing Awards
FROM THE AIA:
Although it measures only 38’ in height, Tiny Tower is organized like a full-scale skyscraper. These small lots are otherwise typically used as expanded backyards or accessory parking. An expanded section that maximizes height under the zoning code as well as depth of foundation creates six levels of usable space. The design promotes vertical living for both indoor and outdoor space, occupying the entire footprint of the site in the required setbacks with a lower level window garden, a second level walk out terrace, and a roof deck. Tiny Tower demonstrates how small scale can feel large in amenity and experience.
Project Credits:
Project: Tiny Tower
Architect: ISA
Structural Engineer: Larsen & Landis
Electrical Engineer: J&M Engineering
Mechanical Engineer: J&M Engineering
General Contractor: Callahan Ward
Stair Fabricator: EnMotion Design