This modest (1,200 sf) family retreat was conceived of as a single gable that spans en-closed living and sleeping areas separated by an intervening dogtrot. This simple form evokes the spirit of nearby vernacular buildings and aspires to be timeless rather than trendy. The roof shelters the most elemental of spaces -- a large room containing living, dining and kitchen areas (along with sleeping space for guests and children), a bedroom, and a bathroom. The dogtrot is integrated into the heart of the house to extend the living area to the outdoors and create a strong connection to nature. In so doing, the house provides a variety of indoor and outdoor living spaces that take advantage of the benign Sonoma County climate. Straw bale construction and other sustainable design measures are used to reduce environmental impacts and to provide a comfortable house that does not require mechanical cooling, even on the hottest days.

SITE PLANNING
The setting is a sloping east facing meadow surrounded by oaks and conifers, over-looking the vineyards of the Dry Creek Valley. The owners wanted to maximize the feeling of space and openness on this small rural parcel. The house is carefully situated on the upper edge of the site to preserve the meadow below and maximize views be-yond. This siting also allows house fits into the site without dominating it.

Steep forested hills to the west and south of the house eliminate the possibility of pas-sive solar heating. These same conditions, however, help keep the house cool on hot summer days. The glassy alcove facing the eastern view is well shaded by a black oak.

DESIGN
The living end of the house is punctuated by two reverse shed dormers, one to each side, that open the sheltering gable to light and to bigger views. The uphill dormer contains the kitchen and opens up to the steep hillside. The downhill dormer overlooks the meadow and views beyond, while providing sleeping space for the owners’ two young children. This bay juts into the landscape, providing a different relation to the outside world –--more open than the sheltered living area, more enclosed than the dog-trot.

The enclosing walls of the house, except at the dogtrot and the two projecting bays, are constructed with straw bales. This surrounding “crust” formed by the thick straw bale walls is broken and pulled apart (like a loaf of bread) at the dog trot. Here the plywood used inside is the wall finish, held between the thick protruding ends of the straw bale walls. Doors and windows are treated as punched openings set deeply within the straw bale (which also helps to shade them) in contrast with the glassier walls of the bays. The color scheme is an “anti-Tuscan” gray on gray with the red of the mahogany win-dows and doors providing a brighter accent.
Inside, a warmer palate prevails, with a yellow lime plaster on the straw bales walls, clear finished birch plywood on the walls and ceilings (no sheet rock is used), and a stained concrete floor. The plywood is also used for the walls of the dog trot.

SUSTAINABLE DESIGN, MATERIALS & CRAFTSMANSHIP
Since passive solar design was not an option on this site, the chief strategy was to keep the building cool during the hot summers without mechanical cooing by employing natural ventilation, superior insulation, and thermal mass. The thin building section, the dogtrot, and disposition of windows all maximize opportunities for natural ventilation. The building envelope was developed using high performance, low-tech insulation -- straw bales and cellulose insulation. The interior plaster walls and concrete floor pro-vide a great deal of thermal mass to dampen temperature swings. By cooling this mass at night (just by opening the windows) the house remains cool through the hottest part of the day. Efficient wood framing (24” on center) allowed for additional insulation and reduced thermal bridging.

Windows are wood, minimizing thermal bridging, and double-glazed with low-e2 glazing. A high efficiency water heater provides radiant floor heating. These measures resulted in a design that beats Title 24 standards by more than 25%, despite the large amount of glazing and wall perimeter for the space enclosed. All of these measures combine to keep the building cool except for the hottest hours of the hottest days. High efficiency, low-water use appliances were selected.
As an outgrowth of our efforts to reduce the amount of wood framing required to per-form a task, we developed a roof assembly design that uses less wood than typical ex-posed wood ceilings. This assembly includes exposed wood framing, but without using the typical double layer of framing (the first layer for structure and the second layer to support rigid insulation.) 1 x 3’s sandwich the 2x 12 rafters and hold up the finished ceiling panels and insulation above, and are detailed to reveal an assembled “beam” that enlivens the ceiling plane.

Other materials were selected for environmental performance and durability as well as for enhancing the design. Criteria included using resources and energy efficiently, prolonging the life of materials and systems, providing a healthy indoor environment, reducing life cycle impacts, and reducing wood use.

> Certified framing and finish lumber, windows and doors (renewable, good for-estry practices)
> 35% fly ash concrete (reduces CO2 emissions)
> Cellulose insulation (recycled content, formaldehyde free)
> Low-VOC paints, adhesives, finishes
> Efficient wood framing (reduced wood use)
> Fiber cement siding (durable, reduced wood use)
> Countertops from recycled glass (durable, waste product)
> Straw bale walls (insulation value, waste product)
> Stucco over straw bales (durable, thermal mass)