A recent report from the global engineering and consulting firm Arup dives deep into the complex relationship between getting fossil fuels out of buildings and creating and preserving affordable housing in Los Angeles, calling for both to be addressed in tandem to secure a resilient future for the city.

Building decarbonization, which refers to the process of powering buildings with clean energy sources instead of fossil fuels and making them energy efficient, is an essential component of LA’s clean energy future and achieving the city’s ambitious goal of achieving full decarbonization by 2050. Currently, LA’s building stock is responsible for 43 percent of the city’s total greenhouse gas emissions. Reducing those emissions involves removing fossil fuels from energy generation, so that carbon intensity of electricity becomes lower and eventually carbon-free, but it must be addressed at the building level too.

What complicates this transition to all-electric buildings is that legacy energy saving programs are often targeted to market rate or single-family housing, meaning the benefits fail to reach those who are low-income, who rent or who live in multi-family buildings.

To ensure that these communities are not additionally burdened by the costs of decarbonization, we must specifically design programs and standards with equitable implementation at their core, such as LA Department of Water and Power’s recently approved Comprehensive Affordable Multifamily Retrofits program. Arup’s work is a critical step forward in informing the design of a system that centers decarbonization efforts around housing affordability and preservation.

An equitable building decarbonization strategy must prioritize low- and middle-income residents experiencing rent burden by ensuring their housing remains affordable, among other key features. Affordable housing comes in many forms, with variations in building attributes, rent structure, types of building owners and level of affordability. This complexity means the decarbonization strategies used for market rate housing cannot simply be replicated because attempting to apply traditional decarbonization policies to affordable housing risks triggering a range of unintended consequences, such as increased rents, increased utility costs and/or displacement.

Here’s how Arup explored the impacts of building electrification on Angelenos, with recommended paths forward:

To better conceptualize these consequences, Arup conducted a series of energy simulations on four multi-family building models — high-density and low-density layouts using construction characteristics typical of 1980-era and 2010-era buildings. Studying post-1978 buildings enabled the technical models to rely on energy performance assumptions grounded in California’s Building Energy Code, Title 24. From there, they evaluated the various implications that fuel-switching measures would have on both renters and building owners. From this analysis, the key takeaways from Arup were:

• Replacing in-place natural gas appliances and equipment to today's all-electric equivalents resulted in utility bill savings across all models studied. However, these savings were not significant enough to offset the first costs of retrofits.
• Building electrical panels and electrical infrastructure will likely require upgrades, especially in older buildings, in order to accommodate all-electric appliances and equipment.
• The first costs of installing fuel-switching retrofits would be more expensive than typical end-of-life equipment replacement due to the electrical upgrades.
• If these installation costs are passed on to renters, they will exceed renters’ utility bill savings and result in higher combined household costs for renters.
• A phased approach — readying the base building systems and upgrading common areas before moving on to unit-by-unit retrofits — would be beneficial.

While Arup’s report focused on a limited set of building electrification measures, it shows the importance of pursuing a comprehensive and equitable building decarbonization strategy for LA’s building stock.

Equitable building decarbonization can yield a wide array of benefits for affordable housing tenants, including lower monthly utility bills, better indoor and outdoor air quality, and fewer medical expenses, to name a few. However, to ensure that decarbonization doesn’t layer additional burdens on already marginalized communities, a systemic approach must include:

• Stakeholder engagement: There needs to be a meaningful stakeholder engagement process that engages subject matter experts on legal, regulatory, financial and technical issues and engages with the affordable housing community around policies that directly affect them.
• Empirical studies: Real-world case studies are needed to better understand cost implications. Data and best practices from these studies should inform program design.
• Mandates: Legislative and regulatory tools are required to drive citywide market transformation, as voluntary actions have proven to be insufficient. Mandates must include affordable housing so renters do not miss out on the benefits of decarbonization, but be designed to specifically protect and provide resources to the sector.
• Investments and incentives: A broad range of public investments and incentives are needed to ease or eliminate costs for owners, tenants and contractors. These investments and incentives should be directed toward housing at the greatest risk of displacement and affordability loss. Incentives targeted at affordable housing should be tied to long-term affordability commitments.

On top of these, there’s a need for technical, financial, regulatory and administrative tools to address the unique barriers the affordable housing sector faces in implementing decarbonization. In particular, housing that serves low-income renters often faces backlogs of deferred maintenance, mold remediation needs, accessibility issues and other habitability concerns that must be addressed along with decarbonization.

These challenges mean that market forces alone will not herald an inclusive and equitable green energy transformation. The benefits of building decarbonization are deeply needed across the housing sector, and the only way to address the twinned demands of affordable housing and decarbonization is by confronting them as one.

This report was funded by the NRDC Action Fund. The information and results contained herein were produced solely by the author(s).

This post originally appeared on NRDC's Expert Blog It was co-authored with Brittany Moffett, resilience engineer, Arup, Heather Rosenberg, associate principal, Arup, and Megan Ross, climate adviser to the city of Los Angeles.