Flag Lots: A Modest Step Towards Increased Urban Density

Most jurisdictions require a residential lot to have a minimum width of required street frontage. For example, I live in an established in-town neighborhood where most of the lots must have a minimum of 75 feet of street frontage. Many of the existing lots don’t meet that minimum — this is not uncommon in older neighborhoods that were built out prior to present-day zoning regulations.

Minimum lot widths can have a chilling effect on the type of smart infill development I believe we need. That was probably the point, right? Community leaders and planners at the time were likely responding to a desire on the part of residents (and urban planning and design trends at the time) to have s detached, single-family home on a nice, wide lot and create more uniformity, more curb appeal, and enhanced “neighborhood character”. Putting aside my strong suspicion of any opposition to development that includes the term “neighborhood character”, I don’t think this is a rational argument anymore. To be fair, there are more practical arguments in favor of minimum frontage requirements and uniform plot lines, including allowing better access for deliveries and provision of government services, such as utilities, police, fire, and garbage collection. I’ll come back to that in a minute.

More recently many planners and city leaders are increasingly recognizing that minimum lot sizes and street frontage requirements, among other factors, have contributed to urban development patterns that hinder infill development, worsen housing supply and pricing issues, promote car dependency, and restrict the potential to increase housing in areas already equipped with sufficient infrastructure for higher density. Maybe these nice, wide lots in urban areas are part of the problem after all.

And that brings me to flag lots. What are flag lots? Sometimes referred to as “pork chop lots”, they are lots that are often shaped like a flag or a pork chop where the often-rectangular portion of the lot (the “flag” or the “meat”) is set back from the road, and a strip of land (the “flagpole” or “bone”, often the width of a driveway), connects the rectangular portion to the street. They look something like this:

[Diagram from Raleigh, NC https://raleighnc.gov/planning/services/faq-raleighs-missing-middle]

Sometimes flag lots are explicitly prohibited in a city’s code, and sometimes the minimum lot frontage requirement is the source of the restriction on flag lots. What do people think about flag lots? A cursory search led me down a rabbit-hole of urban planning discussion boards and articles dating back into the 90s and beyond. It seems that planners have been arguing about flag lots for a long time. Many of them have historically seen flag lots as “bad planning” that leads to disorganized development.

As you have likely already concluded, if you live in a neighborhood with minimum frontage requirements, you probably live in a neighborhood where the creation of new flag lots is prohibited. That doesn’t mean they don’t exist; it only means you can’t create a new one. This may be a missed opportunity; flag lots may provide an opportunity for an incremental density increase that makes more efficient use of deep lots to create additional housing units.

At MicroLife Institute, we are working to create more housing opportunities that respond to current trends in household demographics, a desire for affordable homeownership, and an interest in living in places where people can be less dependent on cars to access amenities, goods, services and employment. We are inspired by communities around the country whose planners are leading the way to allow the creation of flag lots. Check out Raleigh, NC (and this presentation about their Missing Middle 2.0 work), St. Paul, MN, Portland, OR, and Durham, NC.

We are particularly inspired by this example of creative implementation of Durham’s code to create new flag lots and design a 5-unit cottage court. In “How Creative Design Can Turn Strict Zoning Codes into Success Stories” published by Strong Towns on June 28, 2024, Edward Erfurt highlighted a clever solution that designer and incremental developer R. John Anderson shared recently on the highly-recommended Facebook Group “Neighborhood Development”. Taking advantage of Durham’s unique code that permits the creation of new flag lots and has a relatively low (5-ft) minimum width requirement for the “flagpole” portion of the lot, John was able to create a 5-unit cottage court on two adjacent typically-sized lots in Durham. In his design, two of the lots have “typical” street frontage, and three of the lots are flag lots that can accommodate small, one-bedroom cottages. This not only makes smart use of the land but also allows for five fee-simple homeownership opportunities. Bravo!

[Images courtesy of R. John Anderson, accessed at Strong Towns https://www.strongtowns.org/journal/2024/6/28/how-creative-design-can-turn-strict-zoning-codes-into-success-stories]

I have heard the arguments against flag lots. According to some, flag lots add to the number of driveways (and thus increase street traffic) and complicate the provision of utilities, fire and emergency services, garbage collection, deliveries, etc. I think municipalities and… Amazon?... can figure out how to make that work. Fire departments can equip their trucks with 100-foot hoses. (I just checked—a 100-ft double jacket fire hose is $564 at firehosesupply.com.) We can do hard things. As for the aesthetic quality of uniform lot widths, I just don’t think we can afford anymore to let that prevent us from adding a little density to produce more housing.

I’m not saying that reducing minimum lot frontage and allowing flag lots is going to solve our affordable housing crisis. But, along with other legislation that enables missing middle housing development, it can help. Plus, I’m a fan of anything that better utilizes infrastructure we (the taxpayers) have already paid for, like sidewalks, streetlights, sewer and water pipes, etc. There may be some residential zoning classifications in your city where flag lots don’t make sense. But we can update our zoning codes to allow them in appropriate places and regulate them with an eye toward public safety and stormwater concerns. For residential zones that can handle a little more density, I’m firmly planting my flag in favor of flag lots.