A house for climate extremes
Canada is a country with extreme climatic conditions that pose significant challenges to the traditional approaches to passive solar design. The North House is designed with a passively and mechanically conditioned interior that is wrapped by a highly insulated, layered envelope that modulates the house’s response to various climates, solar and shading conditions. The interior consists of a ‘densepack’ of service on the north side of the house, opening to a generous and flexible living space that is fully glazed with a specially developed high-performance glazing system. This flexible framework will allow North House to be customized for different living needs, to be adapted to multiple regions across the country and to take advantage of new technologies and developments in envelope and solar technologies.
holistic solar living
holistic solar living is an approach to making and living that incorporates the energy and benefits of the sun in all ways possible. The consideration of day-lighting, passive systems, microclimate generation, maintenance, food production, solar phase-change material, natural materials produced with the sun’s energy, and solar responsiveness is essential to this perspective. The foremost technological strategy that we are employing is a dynamic shading textile that wraps the glazed volume of the house, managing the passive heating and cooling of the building by offering a range of configurations, from full solar penetration to full shading – always allowing the occupant to choose to expose panoramic views of the landscape, or close the shades completely. Also fundamental to the North House, is the conception of the interior and exterior living spaces as a continuous experience, encouraging the occupant to participate in the landscape as much as possible.
layers | DReSS (Distributed Responsive System of Skins)
In Canada, anyone who spends time in the outdoors camping, canoeing, or hiking, knows that the best way to prepare for unpredictable weather is to dress in layers. Similarly, the North House will be structured and constructed in layers. The outermost layer integrates flexible thin-film photovoltaic technology with passive solar heat management in the dynamic shading textile. The second layer is a high-performance, highly insulated glazing system with an unusually high solar heat gain coefficient to maximize solar gain. Inboard of the glazing system, is an interior shade to moderate privacy and view, without compromising thermal performance. The interior layers, called the Adaptive Living Interface System (ALIS), will be conceived of as a ‘thin’ skin of information systems, responsive to touch, capable of subtle display, and able to mediate interactions between the occupants and the building systems.
Key to the design of North House are the principles of process-based manufacturing. Process-based manufacturing is widely used in automotive, aerospace, and technology industries, but remains in its infancy within the architectural field. Use of prefabrication and component assemblies will support efficient transportation, assembly and disassembly on the National Mall in Washington. North House is conceived as a prototype of mass-customization, which demonstrates a given range of systems and technologies, but in which each system has the capacity to be completely removed and replaced with alternative systems – to allow modification, research, and testing long into the future.
passive solar design
In keeping with a holistic solar approach North House makes use of passive solar design principles to limit the need for mechanical equipment. This principle has guided our approach to designing envelope assemblies, glazing systems, ventilation systems, and daylighting elements. High performance glazing coupled with dynamic shading, can provide passive heating throughout the heating season while also rejecting unwanted solar gains during the cooling season and ensuring a high degree of daylighting control throughout the year. As part of the passive solar design, North House is constructed of a highly insulated and air tight building envelope that is developed with multiple layers. Phase change materials across the floor of North House act as a thermal mass, regulating the interior temperature as effectively as traditional forms of thermal mass, while occupying less space. North House also makes use of passive ventilation by providing operable windows at the east and west façades.
maximum energy production
North House has a goal of producing maximum power throughout the year, in a variety of climatic conditions. Energy production systems are never considered an add-on, but are integrated into the building as much as possible. For this reason, a variety of different types of photovoltaic and solar thermal technologies are integrated into virtually every surface of the building envelope, generating a range of conditions in which PV production and active solar collection can occur. The roof supports a large PV array optimized for a high sun angle complimented by PV cladding on the South, East, and West facades that operate when the sun is at a low angle. Two roof-mounted evacuated tube solar thermal collectors provide domestic hot water and also heat the interior, while the economizer and heat recovery ventilator help to reduce heating and cooling loads. A heat recovery ventilator to help improve the efficiency of the mechanical system.
The North House design includes distributed controllers which operate the heating, ventilation and air conditioning; solar domestic hot water; lighting; shade management; and status/feedback display systems. These controllers require real-time monitoring of various parameters in and outside the house such as temperature, humidity, photovoltaic power production, appliance power consumption, water usage, barometric pressure, solar insolation, and wind speed. These distributed controllers require strategic central coordination which factors in the current state of the house, current weather conditions, short-term weather forecasts, and historical occupant usage patterns so as to maximize energy efficiency. This automated coordination must not interfere with occupants’ ability to temporarily override the system and operate the home as they see fit. Occupant preferences are configured with an advanced Graphic User Interface which also serves as the primary status/feedback display system. The feedback includes, but is not limited to, detailed energy production and consumption information which allows the occupant to make informed decisions in their daily operations that can lead to further increases in energy efficiency.
ease of assembly
When engineering the North House, great care has been taken to design the process of assembly and disassembly as carefully as the building itself. Necessarily rapid assembly and disassembly times in Washington have prompted the goal of designing a high performance building that can be assembled and disassembled many times, while performing optimally in every installation. Each component of the building is designed as an independently stable, shippable, and repairable or replaceable artifact, which has a clearly defined method of shipping, installing, and connecting to its neighbouring components. This has informed every aspect of the building design including our selection of building materials, the structural design, building envelope assembly, overall dimensions, and connections between components. The modular assembly allows for the home to be customized for different occupant lifestyles as well as the different Canadian climates.