The Ridge House

Category: Live
Glen Ellen, CA

The Ridge House is an approximately 1400 square-foot 3-room guest house constructed entirely of cast-in-place, board formed concrete.  The roof is supported by concrete walls on 2-sides and one steel column forming a shell structure with a single sloping folded ridge line over each room.  Special reinforced concrete shear walls provide lateral support with an open-front rigid roof diaphragm.  The rooms are independent volumes, though connected at a single wall element and roof edge, which step down the hill and are slightly recessed into natural site contours.  The sloping roof planes guide the eyes through expansive glazing to view adjacent ridgelines and deep overhangs provide protection from the sun.

Exterior concrete elements are constructed as a non-composite insulated concrete sandwich assembly.  Typically, structural members were placed as the exterior element with architectural concrete exposed at interior spaces. A tapered structural roof section decreases in thickness as the roof extends over full height glazing elements.  Interior design elements integrated into the concrete include a floating cast-in-place concrete vanity, radiant tubing, and tapered glazing geometry.

The clean line, modern aesthetic of the elements necessitated significant coordination between all members of the design team and the contractors, with architectural and structural elements seamlessly integrated to conceal connections and utilities.  Perimeter roof beams were developed to enclose insulation and conceal an integral gutter assembly.  Steel columns, with hidden connections to floor and roof, fit neatly into narrow window mullions to minimize visual impact.

This expression of concrete demanded that visual performance of the concrete be as critical as the structural performance.  Wall control joints were coordinated with board form texture and close attention was paid to concrete mix designs and curing procedures.  The deliberate merging of architectural and structural elements creates a visual simplicity that belies the complex integration of form and function.

Photo Credit: Photo ©Bruce Damonte

Size 1,400 sf
Completed 2017
Construction Cost $1.4M
Architect Mork-Ulnes
Contractor Nordby Signature Homes, Inc.
Concrete Construction Award - Low-Rise Structures Category Winner

American Concrete Institute (ACI), Northern CA-Western NV Chapter, 2020

Merit Award - Residential Design - Built Category

AIA Redwood Empire, 2020

Excellence in Structural Engineering - Award of Merit - New Construction

Structural Engineers Association of Northern California (SEAONC), 2019

Honor Award - Architecture Category

AIA San Francisco, 2019