House Performance - 90% energy use reduction resulting in estimated $192 annually energy bill
Building Envelope - high performance building envelope with triple pane windows and double wall construction
Cost - this 2,200 sf home's construction budget is $330,000
Passive House - We are striving for the rigorous Passive House certification with a PHPP score of 3.57 kBTU/(ft² /yr)
The Shift House sits on a plateau above Hood River and boasts panoramic views of two mountains: Mt. Hood to the south and Mt. Adams to the north. The project is located on a busy street, and in order to shield the residents from the traffic, the program was separated into two buildings. The main house, containing all the living spaces, was set back 70 feet from the street, while an auxiliary building containing a shop and garage were placed directly off of the street.
This separation had the advantage of allowing the auxiliary building to act as a buffer between the street and the house. It also removed the unheated spaces from the main house to allow the heated volume to become more compact.
The House Design
To optimize the use of material resources and maximize solar gain, the building is a south-facing two-story rectangular volume with an optimized surface-to-volume ratio.
The rectangular plan is bisected by an entry foyer and staircase, which divide the house into four distinct areas: living spaces, guest quarters, study, and master suite, virtually eliminating the need for hallways. This layout is then sheared in half along the east-west axis and the two halves are shifted apart by 10 feet. This shift dramatically opens up the living and sleeping spaces to more generous proportions and provides for panoramic views of the surrounding landscape. And with this shift, pockets are formed in opposite corners that allow balconies and porches facing both directions to be integrated into the volume of the building.
With its simple pitched roof and overhangs, the shape, massing, and materials palette of the house references vernacular building traditions, showing that a house with exceptional performance does not have to look out-of-this-world, but can be accessible to the average American.
The design makes the architectural statement that simplicity is an articulation of efficiency, modesty, and beauty: That a simple roof form with less ins-and-outs is cheaper, uses less material, produces less construction waste, provides less surface area for heat to escape through, and provides less opportunity for complicated framing details that lead to thermal bridges and leaks; that an efficiently designed floor plan results in less wasted space, and therefore allows a smaller more modest home to be just as spacious and comfortable as the average American home.
The House Performance
The Shift House incorporates not only physical and spatial shifts, but also represents a paradigm shift in home construction methods and green building philosophy. We were drawn to the Passive House concept because rather than representing sustainability in terms of elusive catch-phrases, it is simply defined by a quantifiable number of allowed energy use; and rather than relying on costly technologies to produce energy, it strives to simply reduce the need for energy in the first place, using simple concepts in an integrative systems approach. The result is simple: no furnace.
Reducing heating energy is reducing heat losses. The house employs superinsulation in order to significantly reduce the heat transfer through the building shell, with special attention given to eliminating thermal bridges. The walls have an R-value of 42 while the roof has an R-value of 60. Every construction joint in the building envelope is carefully sealed to minimize the amount of air that can pass through the structure. High performance triple-pane windows are used to insure that the windows are not the weakest link in the chain.
Reducing heating energy is making use of free heat. The house makes use of passive solar design by facing the majority of windows south to capture the sunlight. This strategy is combined with the use of thermal mass in the form of exposed concrete floors.
The house makes extensive use of intrinsic heat from internal sources – such as waste heat from appliances– as well as body heat from the people and animals inside the building. These heat sources can have a significant impact in a superinsulated building.
To insure a high air quality in the interior, a heat recovery ventilator is employed that not only brings air in from the outside, but also transfers the warmth of the outgoing stale air to the incoming fresh air, thus reusing the building’s existing heat.
Keeping heat out reduces the need for cooling energy. As one of the home's main cooling strategies, all of the south-facing windows are equipped with sliding exterior sunscreens made from horizontal wood slats. Several of the larger windows are equipped with solid wooden shutters that not only provide shade from the sun, but also reduce heat losses through the glass at night. This operability of the house's exterior then becomes a design feature that gives the building its dynamic ever-shifting look.Schedule a Free Consultation