Treehouse
Interior/Exterior Remodel
with Addition
Mercer Island WA
Contractor: Granite Mountain Builders
Photo Credit: Rafael Soldi
Award: AIA 2023 Home of Distinction
Featured In:
Seattle Magazine
Contemporist
Livingetc
American Lifestyle Magazine
Nestled among the Mercer Island trees, this project renovates and modernizes a 1970s Black and Caldwell spec home. Carefully considered interventions preserve the qualities the family valued while introducing more functional, light-filled spaces inside and out.
The approach begins at the entry, where new hardscaping, steel planters, and angled landscape walls guide visitors through the wooded site to a once-obscured front door. A raised concrete porch now clearly marks the entry, while a steel and wood canopy provides shelter, lighting, and a sense of arrival. Layered planting creates privacy and softens the transition between house and landscape.
The main floor was fully reconfigured to better support the daily life of a family of four. An underutilized living room was reshaped to strengthen its connection to the dining area and kitchen. A redundant family room was absorbed into a more generous kitchen and a new home office. Interior partitions were removed to open sightlines and improve flow, while the entry sequence—including foyer, powder room, and storage—was relocated to clarify circulation and orient the primary living spaces toward the outdoors. New windows and sliding doors extend these spaces onto refreshed decks, reinforcing the indoor–outdoor relationship.
Upstairs, the primary suite was reimagined to enhance daylight, storage, and spatial continuity. A new walk-in closet and expanded ensuite bath were created through a modest addition. The bathroom opens to a west-facing deck with views into the surrounding trees. Within, a freestanding tub and double vanity are organized by partial-height walls that maintain openness while allowing light to pass through to a more private shower and water closet, illuminated from above by a skylight.
Alongside spatial improvements, the renovation addresses performance and longevity. New windows, doors, and insulation significantly improve energy efficiency, while updated finishes bring a renewed material clarity to the home
Although the home’s basic form didn’t change, everything else in betw.een did. See below for a BEFORE & AFTER comparison.
“Architects opened the living and dining rooms and the kitchen area and oriented each room to an exterior view, garden or deck. Dead areas were eliminated and room created for a new office and foyer. Improved light penetration and human traffic benefited indoor greenery, sparking a revival of the couple’s wedding gift coffee tree, which now produces 100 beans annually.”
Sean Meyers, Seattle Magazine
Before & After
A refresh of a 1970 Black & Caldwell spec home. While we only made modest changes to the daylight basement of the 3 story home, we gutted and reworked the rest. We redesigned the main floor to create a new living, dining and kitchen space, office, powder and entry foyer. On the upper floor, we reconfigured the master suite, enlarged the master bathroom and added a new ensuite guest bath. For the exterior, we refreshed the decks and created a new entry porch. We reconfigured the pathways, landscape walls and hardscaping leading to the home. A gut and remodel inside and out.
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