[ XTEN Architecture ] Openhouse

Architects: XTEN Architecture
Location: Hollywood Hills, California, USA
Principals: Monika Haefelfinger & Austin Kelly, AIA
Client: Randolph Duke
Contractor: Peddicord Construction
Interior Area: 418 sqm
Total Area: 697 sqm
Project Year: 2007
Photographs: Art Gray Photography

The Openhouse is embedded into a narrow and sharply sloping property in the Hollywood Hills, a challenging site that led to the creation of a house that is both integrated into the landscape and open to the city below. Retaining walls are configured to extend the first floor living level into the hillside and to create a garden terrace for the second level. Steel beams set into the retaining walls perpendicular to the hillside are cantilevered off structural shear walls at the front of the site.

Lateral steel clear spans fifty feet between these beams creating a double cantilever at the leading edge of the house and allowing for uninterrupted views over Los Angeles. Front, side and rear elevations of the house slide open to erase all boundaries between indoors and out and connect the spaces to gardens on both levels.

Glass, in various renditions, is the primary wall enclosure material. There are forty-four sliding glass panels, each seven feet wide by ten feet high and configured to disappear into hidden pockets or to slide beyond the building perimeter. Deep overhangs serve as solar protection for the double pane glazing and become progressively larger as the main elevation of the building follows the hillside contours from Eastern to Southwestern exposure. This creates a microclimate which surrounds the building, creating inhabitable outdoor spaces while reducing cooling loads within. Every elevation of the house opens to capture the prevailing breezes to passively ventilate and cool the house. A vestibule at the lowest point of the house can be opened in conjunction with glass panels on the second floor to create a thermal chimney, distributing cool air throughout while extracting hot air.

Environmental design
Glass in the form of fixed clear plate panels, mirror plate walls and light gray mirror glass panels lend lightness to the interior spaces. These glass walls are visually counterweighted by sculptural, solid elements in the house. The fireplace is made of dry stacked granite, which continues as a vertical structural element from the living room floor through the second story. The main stair is charcoal concrete cantilevered from a structural steel tube. Service and secondary spaces are clad in floor to ceiling rift oak panels with flush concealed doors. Several interior walls are dark stucco, an exterior material that wraps inside the space. The use of cut pebble flooring throughout the house, decks and terraces continues the indoor-outdoor materiality, which is amplified when the glass walls slide away. The building finishes are few in number but applied in a multiplicity of ways throughout the project, furthering the experience of continuous open spaces from interior to exterior.

perspective
Set in a visible hillside area above Sunset Boulevard, the Openhouse appears as a simple folded line with recessed glass planes, a strong sculptural form at the scale of the site. The minimalist logic of the architecture is transformed by direct and indirect connections to the buildings’ immediate environment. The perimeter landscaping is either indigenous or a drought-resistant xeriscape. An outdoor dining area implements artificial turf composed partly of recycled rubber. With the glass walls completely open the house becomes a platform defined by an abstract roof plane, a palette of natural materials, the hillside and the views.