Seattle Housing Policy and Affordability Calculator
In Seattle's climate of rapid growth and high rents, housing affordability has become a critical issue for households at all income levels. Local policies can play a large role in affecting rents by changing the supply of housing and the cost of new development. These policies are often designed to achieve public goals, such as expanding opportunities for community input, reducing carbon emissions, or increasing green space. However, the impacts of these policies on housing affordability are not often directly considered.
This calculator is designed to support discussions about how to develop local policies to balance the impact on housing affordability with other public policy goals. The policy toggles are set to reflect current conditions in Seattle. As you toggle the various policy levers below, the calculator will show estimated changes in the rent for a typical new one-bedroom apartment, along with development feasibility, overall estimated citywide housing production, and estimated shifts in citywide rents.
Click here for a white paper detailing the calculator’s methodology, assumptions, and key findings.
Click on a building typology to select it. Your selection will affect project-level outcomes as each typology has a different construction cost development profile.
Please click on the tabs below to view and adjust the policies levers that can
impact housing costs.
Affordable Housing
Cities often use economic incentives or development requirements to increase the supply of housing affordable to lower-income households. In Seattle, these take the form of Mandatory Housing Affordability (MHA) and the Multifamily Tax Exemption (MFTE).
Affordability Set-Aside
Affordability Level
Mandatory Housing Affordability (MHA) Fees
Tax Abatement
Environmental Impact
Cities are increasingly taking the initiative to address climate change and environmental quality at the municipal scale. As a leader in sustainability practices, Seattle holds both new and existing buildings to a high environmental standard through their Energy Code and Green Factor Requirements.
Energy Code
Green Factor Requirements
Community Impact & Design
Cities often establish touch-points within the development approval process for community members to influence new development. These usually occur during the predevelopment period, which is when projects gain public approval before construction can begin. Predevelopment protocols allow government agencies, local review boards, and community members to determine if proposed buildings comply with local requirements and meet community standards. At the same time, streamlining the predevelopment period makes development less expensive by limiting the ongoing holding costs of property and by decreasing project risk and expensive modifications. Seattle residents also have two additional tools that regulate urban design and form of new midrise and high-rise developments - Open Space Requirements and Floor Plate Restrictions.
Early Community Outreach
Design Review
Permitting Timeline
Floorplate Restriction
Open Space Requirements
Parking Requirements
Public Revenues
New apartments can have a significant impact on a city’s revenue structure and fiscal health. These apartments increase a city’s tax base through property taxes, but they can also increase costs if the city needs to pay for additional infrastructure and amenities for its new residents. Local governments can adjust both the amount of taxes that new apartments pay and the rate at which these taxes escalate over time. Currently, tax abatement in Seattle is used to encourage affordable multifamily development through the MTFE program.