Scalable Tactics for Affordable, Low-Carbon, High-Performance Residential Building Construction and Retrofits *°

DCS ° Polycarb House

FUNDING Kuan and Wu Research Fund for Innovation in Sustainability

DATE
2023-2024
PRIMARY INVESTIGATOR
David Costanza

RESEARCH TEAM Danilo Velazquez
Andreya Zvonar

OVERVIEW Scalable Tactics for Affordable, Low-Carbon, High-Performance Residential Building Construction, and Retrofit is a funded grant that developed a manual of cost-effective, scalable tactics for improving building performance and reducing carbon while retrofitting and building housing in New York. Specifically, the manual targets Ithaca’s Green New Deal and the goal of community-wide carbon neutrality by 2030 and uses a deep energy retrofit as a case study of the required steps and materials necessary to meet the Ithace energy code supplement while also accounting for building carbon, not regulated in the Ithaca Green New Deal. In promoting a scalable low-carbon high-performance residential construction system, the scalable tactics seek to reduce significant greenhouse gas emissions associated with building construction. In addition, the research better prepares individuals, particularly those with the least resources, for a climate-change-impacted world. The project aims to improve the quality of life and the cost of living for those who live in low-performance, high-energy-intensive, carbon-dependent housing.
       
        This project addresses the central challenge architects face today: reducing the source of greenhouse gas emissions associated with building construction. Recent studies show that buildings are responsible for 40% of energy consumption in the United States, noting that more than half of the energy spent goes towards heating and cooling. Another report from the Natural Resources Defense Council suggests that retrofitting existing housing to perform to a high-efficiency level would signify the highest reduction of greenhouse gas emissions in the US. Or, as another study shows, increasing insulation alone in all the single-family homes in the country would reduce up to 80 million tons of carbon dioxide from power plants. Thus, improving building performance and limiting embodied and operational energy both in new construction and existing housing stock becomes paramount if we are to meet the environmental goals posited by the United States government’s ratification of the Paris Agreement.

        However, navigating the transition from low-performance buildings and energy-intensive equipment to high-performance, solar-powered electrified equipment is often difficult and unclear. Coupling this with the variety of building techniques that may facilitate a high-performance building—from 2x4 double stud walls with blown insulation to 2x6 advanced framing with continuous exterior insulation and the range of other possible wall assemblies, for example—further obscures the process for those considering the economic investment. Moreover, building assemblies and high-performance buildings remain largely speculative. With many possible assemblies and strategies consistently debated by building scientists, it is difficult for an architect or builder to understand how to incorporate improvements toward high-performance buildings. 

        To better enable architects and builders to reduce emissions requires restructuring how we build and retrofit the existing housing stock. It demands an understanding of how embodied energy—related to materials, lifecycles, and construction—and operational energy—necessary for lighting, heating, and cooling—can inform an architecture that addresses the environmental impacts of building buildings. 

Thus, this research aims at constructing guides informed through building and testing mock-ups of wall assemblies to demonstrate and educate architects and builders on proven techniques and unpack the nuances and complexities of constructing better buildings. The impact of this work is vast. By improving the thermal performance and air tightness of our envelopes, for example, we can significantly reduce the energy demand for mechanically heated and cooled conditioned space and therefore reduce the fossil fuel-dependent sources of energy that are ubiquitous in residential construction in the United States. Also, shifts in high-carbon materials, such as polyisocyanurate insulation, to low-carbon alternatives require a different approach to designing and detailing. We can push this further by electrifying our energy-dependent equipment with high-performance replacements, such as air source heat pumps, electric heat pump water heaters, induction ranges, etc. Finally, because of the reduced energy demand of a high-performance construction, we can shift our electric power source from the ‘grid’—a combination of fossil fuel, high emissions energy production, and in some cases renewable energy—to local energy production with on-site solar. 

        Under these premises, the project develops scalable tactics for constructing affordable high-performance residential buildings—both new construction and retrofits—that result in manuals of cost-effective techniques for improving building performance and limiting embodied and operational energy. The tactics I aim to construct with this research and funding will help architects and builders sort through the abovementioned complexities. 

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Details 1-20 In Relation To The Position In The Building


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Detailed assembly of the rear deck


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Detailed assembly of the carport ceiling with a triple 24” LVL beam


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Detailed assembly of North West deck


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Detailed assembly of the entrance from the deck



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Detailed assembly of the entrance from the deck


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Detailed assembly of the entrance from the deck


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Detailed assembly of the entrance from the deck