The intent behind minimum parking requirements is to ensure that there is adequate parking for all residents. The effect, however, is that parking gets overbuilt and housing becomes more expensive. Fox Tuttle Transportation Group and Shopworks Architecture released a study titled Parking & Affordable Housing in 2021 which examined how parking was being utilized at income-restricted properties across the Front Range, including 2 properties in Boulder. Across all 19 properties, they found that nearly 50% of spaces were being unused even during peak hours. At a rate of $22,000 per parking space, the total cost of this unused parking was $9.3 million, which is approximately the total project cost of a 40-unit affordable housing building. The cost of building this unused parking is passed along to residents whether or not they own a vehicle.

Regional Transit District (RTD) conducted a study similar to the Fox Tuttle work in 2020 to estimate how much of the required parking was being utilized at residential properties within a 10-minute walk from train and bus rapid transit stations. Across the 86 properties surveyed, they found that parking was overbuilt by 50% at income-restricted properties and by 40% at market rate properties. These properties near transit stops are more likely than other locations to foster a car-free or car-light lifestyle. Overbuilding parking in these locations simultaneously decreases the number of living units that can be built and discourages transit use by centering the personal vehicle. Greater density near transit stops encourages transit use and feeds a positive feedback loop which leads to better services.
The Land Use bill proposed by Governor Jared Polis and state Democrats aims to tackle housing affordability and an undersupply of housing by lifting some restrictions on what types of housing can be constructed (see BHN’s explainer here). The bill outlines provisions that would be present in a model code which municipalities could choose to adopt. If a municipality opts to not adopt the state’s model code, the bill sets minimum standards to which all municipalities must adhere.
The bill as originally drafted would permit accessory dwelling units (ADUs) and middle housing by right on any land currently zoned for single-family housing. It would also require Tier 1 municipalities (including Boulder) to allow multi-family housing by right in transit-oriented areas. Even where these housing types are currently allowed by local zoning codes, they are often difficult and prohibitively expensive to build due to a variety of additional requirements.
One such requirement is a minimum parking requirement. Section 9-6-6 of the Boulder Municipal Code outlines the minimum number of off-street parking spaces required for all housing types in different zones. For example, a 3-bedroom attached unit in RH-2 zoning is required to provide 2 off-street parking spaces. SB-213 in its original form would not allow municipalities to require new off-street parking for ADUs, middle housing, housing in transit-oriented areas, and housing in key corridors.
Cities across the United States have seen the detriment of minimum parking requirements, and they’re taking action. The Parking Reform Network publishes an interactive map of cities and regions which have done away with parking minimums. (Some cities, including San Francisco and Minneapolis, have taken this a step further and implemented parking maximums, putting a limit on the number of spaces developers are allowed to build.) Cities that have ditched parking minimums are starting to see positive effects on housing. Sightline recently published a study looking at the impact of this change in two very different housing markets, Seattle, WA and Buffalo, NY. In Seattle, nearly 60% of all new homes permitted since they got rid of parking minimums in 2012 would have been illegal under the previous code. In Buffalo, that number is close to 70%.
Another finding in the Sightline study is that most new developments still provide some amount of off-street parking. Rather than being forced to build more than necessary, though, they were able to build an adequate amount of parking to meet existing demand. Removing parking minimums doesn’t mean that existing parking will be removed; it simply means that new developments will be allowed to provide only what is needed. This reduces the price for units within developments because residents don’t have to pay for parking that is not needed and unused.
On the Front Range, we can look to a project in Denver for an example of what is possible without parking minimums. The Burrell is a 49-unit condo complex in Denver’s RiNo neighborhood. The City of Denver is not requiring any parking minimum, which led to significant cost savings for the project. Upon completion, the building will be purchased by Elevations Land Trust and 100% of the units will be sold as permanently affordable condos.
Removing parking minimums from our building code would have a positive impact on the amount of housing that we’re able to build as well as the affordability. SB-213 removes costly parking mandates for new development near transit and job corridors.This provision would allow Boulder and other cities across the state to focus on building spaces for people rather than cars. Several amendments were recently added to ensure the bill would have enough support to make it out of committee, including removing parking mandates.. But the bill goes to the House this week, and the elimination of parking requirements along transit and job corridors could be restored. Contact your House of Representatives member today to voice your support.
In Boulder, these are our state representatives:
Representative Judy Amabile, judy.amabile.house@coleg.gov, 303-866-2578
Representative Junie Joseph, junie.joseph.house@coleg.gov, 303-866-2915