Invisible sustainability: A design approach that exceeds 2030 targets
Using integrated passive design and advanced energy modeling, this small firm strives for simple methods and design freedom while meeting the 2030 Commitment
Imagine it is minus-40 degrees Fahrenheit. From a space of perfect thermal comfort a blizzard dances around you, as if you were in a snow globe. You feel a seamless connection to your natural surroundings, yet no active heating is being used. In fact, this near-zero energy building meets the 2030 Commitment without high-tech gadgetry or renewable energy systems. The focus is purely on the poetic sense-of-place that the architecture and landscape create.
I like to call this “invisible sustainability.”
From the extreme cold climate of northern Minnesota, my architecture and research firm COULSON has been refining this approach since 2008, meeting the highest levels of sustainability using simple, invisible methods, without impacting the aesthetic creativity and elegant simplicity we strive for. We began with the groundbreaking design of the University of Minnesota Bagley Classroom, a LEED Platinum and AIA COTE Top Ten Award recipient, and have gradually advanced to achieve greater design freedom, transparency, cost control, and minimalist details in our recent residential, office, educational, and cultural projects.
As an AIA 2030 signatory firm we are committed to meeting 2030 targets for all our work; we have a portfolio average of 89 percent pEUI overall and 100 percent for 2016. For comparison, the 2016 target for firms was 70 percent. Our passion for the environment is not only technical but extends to the experience of nature, which is an essential element in our designs. We insinuate our buildings into the landscape to live seamlessly and lightly with its magnificent beauty, while using passive and natural methods to achieve resiliency and energy freedom.
Taking both a rigorous and an experimental approach, we respect the details and fundamentals but allow time to explore the question, “What would happen if we tried this?”
With a conservation-first, keep-it-simple approach, we focus on the building envelope and elimination of heating and cooling loads. This alone can achieve a 70 -to-80 percent primary energy reduction without renewable energy systems. The option for zero energy is easily within reach. A tiny, low-tech photovoltaic system integrated or concealed in the architecture can satisfy the remaining energy demand without impacting style or ease-of-use.
The essential tool is advanced energy modeling. We incorporate it into our daily design process at all project phases. Taking both a rigorous and an experimental approach, we respect the details and fundamentals but allow time to explore the question, “What would happen if we tried this?” We’ve found that question to be more affordable and fluid when we’re doing energy modeling in-house; it provides us a joy in creative discovery. From it, we’re writing a new language for green building.
It’s thrilling to discover standard assumptions and rules-of-thumb are often upended with surprising results that are only possible through modern modeling tools and highly accurate climate data information. Because designing for climate, and understanding it, is critical.
Energy modeling: A passive, integrated approach
Integrated into our creative design process, energy modeling is used to analyze the methods and details that achieve deep energy reductions. We focus on solutions that are permanent and passive:
- Compact building form
- Continuous super-insulation
- Winter passive solar heating
- Summer shading
- Elimination of thermal-bridges
- High-efficiency mechanical ventilation
These items alone can achieve 2030 and near-zero energy.
Avoiding the trap of technology-creep, this passive approach simplifies and liberates. There is no dependence on complex systems that demand constant monitoring, maintenance, and eventual replacement. With the elimination of traditional heating and cooling systems, architects can achieve thinner floor lines and elegant views without HVAC blight. Energy reductions are built-in and will last the lifetime of the building.
One example is MH House, a suite of modern glass pavilions for residential and office use in downtown Duluth, Minnesota. The project has a 90 percent pEUI reduction without any renewable energy system and a peak heating load of just 2000 watts for the entire site—that’s one hairdryer. This is supplied with a simple 500-watt electric radiant panel on each floor. An energy recovery ventilator provides continuous ventilation. Floor-to-ceiling glass captures the winter sun and frames the expansive vistas of Lake Superior, while the exterior sunshade structure and surrounding trees block unwanted heat gain.
The highly compact building form—with just 8 feet floor-to-floor—provides a dramatic reduction in exterior surface area and heat loss and gains, thereby eliminating traditional heating and cooling systems and perimeter heating. The construction approach is a pre-fabricated kit-of-parts where the exposed construction is a central part of the aesthetic. This includes expanded polystyrene insulation surrounding a concrete slab, steel and timber structure, triple-pane insulated glass, and vacuum insulated panels, along with local and reclaimed finish materials—all of which are cost effective and readily available.
We want sustainability to be invisible: to merge with mainstream architecture as a standard element of design excellence, with the primary focus on the emotional atmosphere and experience that architecture creates. Is it a green building? No one can tell, and we won’t need points or plaques. AIA’s 2030 Commitment, with its inclusive and neutral approach and ability to touch the entire profession, is a wonderful vehicle to drive change and bring sustainability into the mainstream. That is why we are an AIA 2030 signatory firm. It’s also a platform to share our knowledge and data, so those who are in the early stages of sustainable practice can use our experience as a springboard to leap forward.
How might you create invisible sustainability?
COULSON is dedicated to meeting the highest level of sustainability and design excellence. As an AIA 2030 signatory firm, all their design work meets the 2030 Challenge with a firm portfolio-average of 89 percent pEUI reduction overall and 100 percent for 2016. Explore COULSON case studies here.
Carly Coulson, AIA, is the design principal and founder of COULSON. She was recognized with an AIA COTE Top Ten Award for the University of Minnesota Bagley Classroom, leading the design of this LEED Platinum-certified and Passive House building.