Nestled on a secluded tree-lined street in Sag Harbor, New York, a late-1800s, historic home conveys a warm, welcoming presence. Seen from its gravel driveway, the home’s white-shingled facade and new landscape conceals a rear addition. The newly formalized architecture and landscape firm Emilia Hammett (formerly KTISMA Studio) spearheaded the design effort for the addition as well as the picturesque garden.
Gravel continues from the driveway to the back of the house, where the designers used it to create narrow paths through the new well-kept English Garden. Spanning 12,250-square-feet on the half-acre property, the verdant garden is filled with colorful flower beds and a repurposed lap pool. It also features a cutting garden.
The 1-story, 1,100-square-foot contemporary addition extends off the rear of the village house, replacing a former extension that mimicked the revivalist style.
“The twist was the aesthetic: Rather than designing in the revival style, the clients wanted something modern,”Jonathan Chesley, founding principal at Emilia Hammett, shared with AN Interior. “We loved this constraint and moved forward designing something contemporary with inspiration and connection to the historic home.”
The facade is wrapped in Alaskan yellow cedar shingles. Their coursing is aligned with the cladding of the historic home, but at a smaller height: There are two rows of new shingles for every one on the existing house. The massing of the addition further aligns with the home’s proportions and roofline and is kept low to better hide it from the street. Hagerman Builders is the project‘s general contractor, and Land Space is its landscape contractor.
A connection to the gardens grounds the new, modern style. The line between inside and outside is blurred, most explicitly through extensive floor-to-ceiling windows that are over 9 feet tall.
“The gardens were designed in conjunction with the extension. This is one of the key elements of this project and what is unique about our firm,” said Chesley, who runs the firm with his partner Alexandria Donati, the landscape principal of the studio. “At one point, the garden responds to the landscape and then the next, the architecture responds to the garden.”
This is particularly true when accessing the new space: Designing the landscape and addition concurrently enabled the studio to create a dramatic promenade around and into the addition.
Within, an open floorplan combines the kitchen, dining room, bar, and living room. Throughout, a minimalist design, neutral color palette, and natural materials unite programming. In the kitchen, white built-in cabinets with frosted glass and a matching island form a mainly monochrome area. Marbled countertops and backsplashes add a touch of depth, in addition the texture of the plastered ceiling. Below, limestone flooring is used both inside and out.
The flooring continues throughout the great room, where off-white soft seating creates a living room. The studio worked with Chiara de Rege, who served as an interior designer. An expressive, rounded coffee table sits between two organically curved sofas. The wood is echoed in the nearby dining table. Outside, a shaded pergola creates another space to gather.
This residential project, a union of architectural and landscape expertise, is an important one for Chesley and Donati: It was their first professional collaboration. The couple, who are partners in life and work, recently relaunched their Ojai- and Brooklyn-based practice as Emilia Hammett. (The firm’s name combines the leaders’ middle names.) Previously, they worked as KTISMA Studio, a practice that was recognized by AN in its inaugural Twenty to Watch list in 2025 and published by AN Interior. Chesley gained experience as an architect at Selldorf Architects, while Donati was the design director at Miranda Brooks Landscape Design.
Now, after rebranding, the bicoastal design practice stands ready to deliver architecture, interiors, and landscape. Its work is shaped by a “sensitivity to place; a desire to create spaces that feel at once timeless and deeply of-the-moment; and a belief in the connective threads between art, work, and life.” Taking Emilia Hammett’s Sag Harbor project as an indicator, Chesley and Donati are off to a promising start to accomplish this ambition.
