Many major metropolitan areas across the country face critical housing shortages that cause surging home prices and real concerns about affordability and quality of life. The unsustainability of suburban sprawl, coupled with land supply constraints, causes states and local governments to increasingly look to infill and redevelopment to help address the crisis.
Urban infill refers to the development of vacant or run-down land in higher-density areas for new construction. It offers many advantages and benefits: more housing in desirable and walkable areas; community revitalization; sprawl and traffic reduction; proximity to employment, existing infrastructure and amenities; and economic development. An infill site also comes with unique challenges that are different from that of greenfield sites. Often, these sites remain undeveloped for a good reason. Site constraints, labyrinthian zoning and permit approvals, neighborhood resistance, and funding obstacles have hindered many a well-intended firm from taking these projects on.
Drawing from our team’s experience, we’ve outlined several key factors to consider, potential pitfalls and barriers to success, and opportunities for innovation and creativity.
Zoning and Land Use
The best-laid infill plans can get delayed and derailed by antiquated zoning restrictions. Parking requirements, building heights, density, and land use designation are among the chief areas that need addressing. Zoning change can be a difficult legislative undertaking, which is why some cities are creating successful workarounds to streamline the approval process.
Overlay districts are special zoning areas that lie on top of existing zoning that modify existing requirements. Overlays create more regulation; however, they can also offer flexibility and exceptions. For example, a zone with a two-story building height requirement may include an overlay in some areas that allow for up to four stories, creating opportunities for development that would otherwise be impossible under previous conditions.
By-Right Zoning Improvements
Cities are also looking for ways to increase efficiency in by-right zoning to reduce costly project-by-project decision making. And sometimes, all it takes is collaboration and creativity, as documented in an Urban Land Institute case study about the Oslo apartment rental development in Washington, D.C., where the developer and architect had to rely upon the specifics of the zoning to drive the design and gain approval. Seek out local governments that have modernized their zoning practices to address and encourage revitalization and redevelopment.
Infill projects often involve brownfield sites, which are parcels of previously developed land and everything that sits on it from mineral rights structures. In urban centers, brownfield sites are usually old manufacturing buildings, dry cleaners, or gas stations. Brownfield sites bring their own set of considerations, including demolition requirements, environmental remediation, and financing. The EPA has outlined various insurance, funding, and federal and state tax incentives to help offset brownfield development costs and reduce liability.
Utilities and Infrastructure
Infill sites are typically located in established neighborhoods and may be able to utilize existing utility access and infrastructure. The cost savings could potentially mitigate some of the higher initial capital costs for infill projects. And while there’s the possibility of additional fees associated with expanding utility access to accommodate higher density, retrofitting is still less expensive than greenfield infrastructure development.
Greenfield development brings numerous infrastructure requirements, including streets, public transit access, schools, and parks that add to a developer’s cost in the form of impact fees. Because of their urban or suburban location, infill sites already have most if not all of the necessary infrastructure to support them.
Emergency and Commercial Vehicles
Depending on how the site was previously used, emergency and commercial vehicle access may need to be considered. These planning issues can be resolved through zoning overlays, as mentioned above, and most municipalities have street design guidelines for trucks and large vehicles. The local fire department should always be contacted in the early stages. Understanding fire codes and vehicle access requirements from the start will help prevent surprises later.
Soil and Drainage
Physical site defects can limit the feasibility of infill projects, including inferior soil quality and poor drainage. Soils with high shrink and swell from inadequate drainage can affect the structural integrity of reinforced concrete structures common in smaller and narrow infill sites. Thorough testing is critical during initial evaluations, especially for brownfields that require environmental remediation and cleanup.
Parking and Traffic
When people think of higher density housing, they assume more parking and traffic congestion comes with it. But that doesn’t have to be the case with infill. Existing infrastructure could include parking garage access, sharing, or expansion. A focus on transit-oriented infill projects can reduce or eliminate car usage among residents through alternative transportation, including light rail, bus, bike, and ride-share.
For more on urban infill, check out our blog on 10 design tips for urban infill architecture. An experienced architectural firm well versed in smart growth and urban infill development can help design projects that align with the context of the existing neighborhood, navigate the approvals process, and gain community acceptance.
If you’re ready to evaluate an infill project, we’re prepared to help! Contact us at 303.442.5882 or via the form below.