H: Paper Session_C5: Ecovillages, Urban Infill and Corner Lot Housing
Can Danish Ecovillages Demonstrate a Path to Reduce Domestic Energy Use?
1University of Washington, Seattle, United States of America; 2Aalborg University, Copenhagen, Denmark
Household energy use significantly contributes to global carbon emissions. Despite the urgent need to reduce carbon emissions, domestic energy consumption in Denmark is decreasing at a slow rate. This study explores why top-down policies aimed to reduce domestic energy consumption are producing marginal results. We also contrast this approach with Danish Ecovillages, which our findings suggest use much less energy than conventional housing. We also explore how social norms of energy saving emerge within Danish Ecovillages, and how this might represent a pathway to reduced domestic energy consumption.
This study presents findings from field observations and interviews conducted between September and December 2017 of seven Danish Ecovillages. Observations of social practices and architectural design are discussed. Detailed, self-reported household energy data were also collected from three Ecovillages and compared to a baseline of similar Danish homes. Our findings show a significant reduction in heating and plug load consumption in the Ecovillages. When compared with a typical Danish household, the three Ecovillages used 24% to 73% less energy.
This paper finds that the emergence of social norms that promote energy saving everyday practices can partly explain the observed reduction in energy consumption. This paper explores how Danish Ecovillages overcome hurdles faced in mainstream society for developing social norms that reduce energy use, mainly through strengthening social relationships between norm beneficiaries and designing the built environment to align with community values.
The Checkerboard Charleston House; A Model for Passive Urban Infill Housing
Thomas Jefferson University, United States of America
Large sections of US cities still contain an abundance of vacant land leftover from the flight to the suburbs. The fringes of this land are slowly being developed with larger scale versions of the row houses they replace. But the way we live now is much different than when those row houses were built over 100 years ago. Instead or rebuilding new homes that (like their predecessors) suffered from a lack of sunlight, fresh air, open space; should we consider how to rebuild the city with passive houses that are brighter, healthier and more energy efficient? The Checkerboard Charleston House (CCH) is the latest version of a research /design project that studies how urban homes can be designed to allow more sunlight for heating and daylighting, cross breezes for ventilation, natural shading, PV power and a highly insulated envelope. Starting with the proven urban row house pattern, but sliding and flipping alternating houses back to face a new interior lane, a checkerboard pattern is created. Now, instead of a small “postage stamp” sized back yard, each home gains a larger south facing side yard with access to light, air and green space for almost all rooms. This pattern is similar to the classic Charleston House typology, with its galleries and access to a side yard, so served as framework for the new design. The galleries provide natural shading for large glass doors and windows along the south façade to promote passive heating, cooling, daylight. The slope of the gable roof is set at the angle of the equinox sun to maximize PV power production throughout the year. The 400 square feet of panel space provides more than enough to power from medium efficiency panels to supply the recommended 7 kW system. Passive House principles are utilized with prefabricated modular construction to maximize energy efficiency while minimizing costs. Energy and daylighting models using Sefaira software are being tested to compare a standard row house to the CC House model.
Being dependent on the sun, the orientation of the homes is critical. An optimum site would contain plenty of open land, a majority of north-south oriented streets and block widths that are within a range that allows for the pattern to fit. Detroit was used as the test case because of its abundance of vacant land (over 16%) that meets these criteria extremely well. One expectation was that the larger side yard would greatly reduce neighborhood density, but when compared to the existing lot sizes, the CCH models have slightly more dwelling acres per acre; and they are much denser than the new suburban style homes being built in the city. These initial studies indicate the CCH warrants further study as a potential strategy to sustainably rebuild our cities.
Intricate Compatibility: Study of a Hillside Lot in Tokyo
University of North Carolina at Charlotte, United States of America
In 2018, architect Akihisa Hirata in collaboration with structural engineers Masato Araya and Atsuhiro Sao of Oak Structural Design Office introduced a novel, stepping galvanized steel frame system for the construction of three intertwining living units on three different levels on a small, corner lot in Minami-Otsuka, Tokyo. In this dynamic spatial eco-system (1), consisting of three overlapping and staggered offset apartments, the building opens up to the outside world as a kind of public performance. The rotating slope of the corner site creates a system of forces that rise and revolve. This is made evident by the alternation of interior and exterior spaces of construction and vegetation in relatively stable equilibrium, what Hirata calls ‘karamari-shiro’ or intricate compatibility. Galvanized steel columns emerge from the ground and folding landscape while the building bends and folds to accommodate pallets of roof sod. Daylight filters through sky apertures and volumetric voids in three directions. At night, plant lighting illuminates the underside of galvanized corrugated metal sheathing, fusing the vegetal with the industrial in surprisingly novel ways.
The project presented in this paper is part of a body of ongoing design research that investigates environmental architectures and eco-spatial system thinking. The idea of using vegetation, permeability, light and air as a form of connection between private space and public performance has been previously explored by Hirata for art merchant Taka Ishii in Toshima-ku. Despite the increased focus on sustainable design globally, and the certification systems that undergird them, there is need for further study of the performative relationships between site, building and landscape in the city. Through a series of diagrams, details and photographs, this paper presents field research of a topologically complex hillside site that introduces new forms of dwelling and inhabitation (2). With increasing need for affordable, livable, and humane urban housing, the intent of this research is to uncover the principles, strategies and methods employed in an effort to re-establish novel solutions for addressing the growing need for healthy, open, light-weight and transformative urban housing. Results from this study suggest that integrated eco-system design and the complex overlap between construction and vegetation remain an untapped source for social and environmental innovation.
(1) British botanist Arthur Tansley defined “eco-system” to mean a particular category of physical systems, consisting of organisms and inorganic components in a relatively stable equilibrium, open and of various sizes and kinds (1922).
(2) Building the Slope: Hillside Houses 1920-1960; Dominique Roulillard conducted a study of the design principles and techniques used by architects to build houses on hillsides in California.