After moving from Chicago to the cozy college town of Ann Arbor, Sharon and Robin were eager to infuse a touch of urban sensibility into their new home. The 1914 protected-status house had a detached two-story garage that the couple felt could be vastly improved with a contemporary addition that connected the two structures.

$1,182.84 Building Permits & Fees	$822.50 Project Management	$655.50 Material Acquisition
$430 Mobilization & Site Maintenance	$908 Waste & Recycling	$1,198.50 Demolition
$8,953.50 Excavating & Foundations	$10,564.65 Rough Framing	$8,512.18 Windows, Doors, & Screens
$2,745.50 Roofing & Water Drainage	$4,394.74 Rough & Finish Plumbing	$4,701.58 Rough & Finish Electrical
$2,442.53 Insulation	$1,985 Drywall	$9,139.41 Exterior Cladding & Carpentry
$2,828.49 Painting & Finishing	$1,895.73 Flooring, Tile, & Stone	$2,666.34 Carpentry & Cabinets
$5,500 Patio & Driveway	$3,750 Retaining Wall & Raingarden	$305.50 Punch List & Final Cleanup
$8,980.33 Additional Services
Grand Total: $84,562.82

Sharon is a University of Michigan professor of architecture, and she’s well aware of Ann Arbor’s strict regulations on altering historic district-protected buildings. She reached out to Kasey Vliet, the Principal of KASE Studio, who had served as a teaching colleague at the university and shared her vision for contemporary architecture.

“The City of Ann Arbor has a strict and monitored process for altering or adding on to historic district-protected buildings,” says Vliet. “The primary criteria for an addition is that it not overwhelm the existing building by its location or massing. Secondly, the addition’s form, materials, detailing, and color is required to either exactly match that of the existing building, or be distinctly different from it. We chose a contemporary design which differentiated itself from the original house in a neutral way.”

Combining requests from the clients and the historic district, KASE Studio crafted a multifunctional 206-square-foot addition with an abundance of glazing—to promote views of the original architecture and the outdoors—that could be easily removed should a future owner wish to return the house to its original form.

“The design is thus tectonic, and articulated as a breezeway—with a thin exterior steel structure and minimal structural connections to the existing house structure,” explains KASE Studio. The floor plan geometry was partly informed by the existing setback lines. “Instead of bearing on the existing house foundation, new columns sit atop a new foundation and support a header beam along the shared existing wall.”

In addition to a contemporary and minimalist design, the new addition offers more than just a covered walkway between the house and the garage, which contains Sharon’s home office on the second floor. Since there was no bathroom on the ground floor of the house, the clients requested a powder room as well as a bistro nook where they could enjoy garden views.

One of the most challenging aspects of the design was navigating the significant elevation drop of around four feet from the ground floor to the garage entrance, across a distance of approximately 20 feet. Six steps were installed with the maximum rise allowed by the state building code to create a seamless extension from the kitchen floor to the new addition while keeping the hallway’s concrete floor level with the existing garage floor.

Given all of the north-facing glass, the steel-clad addition is primarily used in times of temperate weather and is separated from the main house with a thermal curtain for energy efficiency.

“Thermally, the addition is conceived as an extended vestibule into the main house, and thus is not heated or cooled to the same temperature as the main house,” notes Vliet. “It is passively ventilated for cooling with ground-level operable windows and heated with two hydronic baseboard heaters. The powder room has its own electric baseboard heater and operable window for ventilation to keep the space slightly warmer than the rest.”

“Sharon and Robin now spend a huge portion of their at-home time in the addition—using the little nook for coffee and reading, and dining outside whenever possible,” says Vliet. “With a small 200-square-foot addition, the house is transformed to be more connected to its landscape and the adjacent home office and garage.”

Related Reading:

15 Modern Additions to Traditional Homes

Budget Breakdown: A Seattle Couple Build a Backyard Addition For $413K

Project Credits:

Architect of Record: KASE Builders, LLC / @kasestudio

Builder / General Contractor: KASE Builders, LLC / Kasey Vliet

Structural Engineer: SDI Structures