Appropriate Repair and Retrofit for Carbon Reductions: OSCAR

The APT Technical Committee on Sustainable Preservation (TC-SP) recognizes the urgent need and opportunity to address the climate crisis through the care for and appropriate retrofit of our existing buildings. Since 2004, the TC-SP has been facilitating technical information exchange and promoting best practices for climate action through the responsible stewardship of our built heritage and cultural landscapes.

Approximately 40 percent of global carbon emissions are attributed to buildings and may be considered in terms of embodied and operational carbon. Many strategies are available to reduce emissions. Embodied carbon can be addressed by extending a building’s lifespan through careful consideration of durability, maintenance, and repair. Material selections for repairs and retrofits affect upfront carbon emissions. Redevelopment of the deconstruction, salvage, and reuse economy helps keep our materials and carbon investments in use.

Well-considered building retrofits, especially of the building envelope and systems, can reduce operational carbon emitted in the pursuit of thermal comfort, lighting, and daily activities, through sound building science principles, strategies like Passive House, and targets like zero net carbon design. (passivehouse.com)

Climate-specific, low-carbon strategies may be found in the embodied wisdom, or “Inherently Sustainable Features,” of the design of our built environment for thermal comfort, durability, and resilience.

There is a recognized, urgent need for readily available guidance for existing buildings of all levels of historic significance, in multiple climates, and in many typologies, traditions, and materials. A sharing of collective wisdom, across areas of expertise, is needed to mobilize and effectively address both the necessary carbon drawdown and the repercussions of the climate change already underway.

To address this need, the APT TC-SP has developed the Online Sustainable Conservation Assistance Resource (OSCAR). (oscar-apti.org; apti.org/sustainable-preservation) OSCAR is a qualitative informational resource, designed to provide relevant guidance for building preservation and operational carbon improvements. It is a growing, searchable database of best practices, distilled into summaries of key points and linked to cited references with more in-depth information.

OSCAR is organized as a visually engaging collection of “Action Cards,” each with concise information about a given topic in a clear, consistent format. Action Cards are organized into categories, including Preservation (Embodied Carbon), Energy (Operational Carbon), and Inherently Sustainable Features. Within each category they may be searched by building component, with a further breakdown by assembly types and materials. The content on each card is noted for its applicability to each of four general climate types.

The Action Card databases are browsable and facilitate a further, personal distillation for project-specific information, by way of the Project Builder. In the Project Builder, Action Cards may be saved to personal Collections, where multiple combinations may be explored, such as for varying levels of intervention for a given project. In aggregate, Collections for all identified building components facilitate the creation of a holistic, “Whole Building Ecology” of relevant reference information to inform a design approach. Collections may be saved in a printable format to share, such as with a design team, owners, stakeholders, and/or regulatory agencies.

In its ongoing development, OSCAR fosters engaging, crowd-sourcing conversations, and taps into the collective expertise of the APT membership. It is building the expertise of the interns and emerging professionals assisting with its development and serves as a growing repository for use by a wider audience, including peers and colleagues across the building professions.