Infill development

What Is Infill Development?

Infill development is a real estate and urban planning strategy that involves building new structures on vacant or underutilized land within existing urbanized areas, rather than expanding into undeveloped "greenfield" sites on the periphery of a city. This approach falls under the broader category of urban planning and aims to maximize the use of existing infrastructure, promote efficient land use, and revitalize established communities. Infill development seeks to optimize existing space by adding density, often through projects like constructing new housing, retail spaces, or mixed-use developments on empty lots, abandoned properties, or parcels with outdated structures.

History and Origin

The concept of infill development has gained prominence as urban areas have grappled with the challenges of sprawl, infrastructure costs, and environmental preservation. While the practice of building within existing settlements is as old as cities themselves, the modern emphasis on "infill development" as a deliberate planning strategy emerged more strongly in the latter half of the 20th century. This was driven by a growing awareness of the negative impacts of unchecked suburban expansion, such as increased commuting times, loss of open space, and strain on public services.

Organizations like the U.S. Environmental Protection Agency (EPA) have championed "smart growth" principles, which strongly advocate for infill development as a key component. Smart growth aims to create sustainable communities by promoting compact development, walkable neighborhoods, and the preservation of natural areas.¹¹ The American Planning Association (APA) has also been a vocal proponent, noting that infill strategies can streamline regulations, support land use reform, and incentivize local innovation in addressing housing needs.¹⁰ For instance, New York City adopted an infill strategy to generate income for its public housing authority and promote mixed-use developments.⁹

Key Takeaways

• Infill development involves constructing new buildings on vacant or underutilized land within already developed urban areas.
• It is a core principle of smart growth and sustainable urban planning.
• The strategy aims to maximize existing infrastructure and reduce urban sprawl.
• Infill projects can include residential, commercial, or mixed-use developments.
• Potential benefits include revitalizing communities, increasing housing supply, and reducing environmental impact.

Interpreting Infill Development

Interpreting infill development goes beyond simply recognizing new construction. It involves understanding its role in shaping urban landscapes and addressing various societal needs. Successful infill development integrates new structures seamlessly into the existing urban fabric, respecting the character of the neighborhood while introducing new vitality. It is often seen as a way to increase population density and provide a greater variety of housing options, from single-family homes to multi-unit buildings.

The implementation of infill development can also indicate a city's commitment to sustainable practices. By leveraging existing public infrastructure like roads, water lines, and public transportation, infill development reduces the need for costly new infrastructure extensions typically associated with greenfield development. This approach can also support local businesses by increasing the customer base within established commercial areas.

Hypothetical Example

Imagine a mid-sized city, "Riverside," that has experienced significant outward growth over several decades, leading to traffic congestion and strain on its peripheral services. Within Riverside's older downtown area, there are several abandoned industrial lots and underutilized commercial properties.

A developer identifies a two-acre parcel, formerly a dilapidated warehouse, located near a public transit hub and an existing retail district. Instead of building a new suburban housing tract, the developer proposes an infill project. The plan is to demolish the old warehouse and construct a five-story mixed-use building. The ground floor will house small retail businesses and a cafe, while the upper four floors will feature 80 residential units, including a mix of one- and two-bedroom apartments.

This infill development project leverages the existing transportation network, attracts new residents to an underpopulated area, and provides new commercial opportunities. The new residents will likely utilize nearby shops and services, contributing to the local economy. Furthermore, the increased density on this previously unproductive land helps to alleviate pressure for new construction on valuable green space outside the city.

Practical Applications

Infill development is a versatile strategy applied across various aspects of urban development:

• Housing Affordability: By increasing the supply of housing within existing areas, infill development can help address housing shortages and potentially improve housing affordability. Cities like Portland, Oregon, have seen significant increases in middle housing permits, such as duplexes and triplexes, due to residential infill projects aimed at providing more affordable homeownership opportunities.⁸
• Economic Revitalization: Repurposing vacant or neglected properties through infill development can revitalize declining neighborhoods, attract new businesses, and boost property values. This can lead to increased tax revenue for municipalities without expanding their physical footprint.
• Environmental Sustainability: Infill development is a cornerstone of environmentally conscious urban planning. It reduces vehicle miles traveled, leading to lower carbon emissions, and preserves agricultural land and natural habitats from development. The EPA highlights that compact development can generate more revenue per acre due to efficient land use and can reduce infrastructure costs.⁷
• Infrastructure Efficiency: By concentrating development where infrastructure already exists, infill projects reduce the need for expensive extensions of utilities, roads, and public services. This makes more efficient use of public funds and can lead to lower operating costs for municipalities.

Limitations and Criticisms

Despite its numerous benefits, infill development also faces limitations and criticisms:

• Higher Costs: Infill projects can sometimes be more expensive than greenfield development due to factors like higher land acquisition costs, the need for demolition, and potential environmental remediation, especially on brownfield sites.⁶ Addressing existing infrastructure deficiencies or navigating complex zoning regulations can also add to expenses.
• Community Resistance: Existing residents may express concerns about increased traffic, loss of neighborhood character, strain on schools, or changes to property values. This "Not In My Backyard" (NIMBY) sentiment can lead to lengthy approval processes and even project cancellations.
• Infrastructure Capacity: While infill development leverages existing infrastructure, intense infill without proper planning can overwhelm outdated or undersized systems, such as water, sewer, or transportation networks, leading to new challenges.
• Limited Impact on Affordability: Some critics argue that while infill development increases housing supply, it doesn't always translate directly into more affordable housing, particularly if the new units are market-rate and cater to higher-income residents. The increase in land value due to densification can sometimes negate the cost savings from increased density.⁵

Infill Development vs. Greenfield Development

The primary distinction between infill development and greenfield development lies in the type of land utilized.

Infill development focuses on efficient land use within established areas, aiming to rejuvenate communities and maximize existing resources. Greenfield development, conversely, involves expanding outward, often leading to lower densities and reliance on new infrastructure. While greenfield development might offer lower initial land costs, the long-term societal and environmental costs, including increased commuting and resource consumption, can be substantial. Understanding the differences is crucial for effective land use planning and sustainable urban growth.

FAQs

What are the benefits of infill development?

Infill development offers several benefits, including more efficient use of existing infrastructure, reduced urban sprawl, revitalization of declining areas, increased housing options, and environmental advantages such as lower transportation-related emissions.³, ⁴

Is infill development always more sustainable?

While generally more sustainable than greenfield development, the actual sustainability of infill development depends on various factors. Proper planning is essential to ensure new construction is well-integrated, minimizes negative impacts on existing residents, and does not overwhelm local infrastructure.

What are common challenges in infill development?

Common challenges include higher land acquisition costs, potential for environmental remediation (especially on former industrial sites), community opposition, and the need to navigate complex zoning and permitting processes.

How does infill development impact housing affordability?

Infill development can help housing affordability by increasing the overall supply of housing, particularly if it includes a mix of housing types and price points. However, if market forces drive up land values significantly, the new units may still be expensive.²

What role do local governments play in infill development?

Local governments play a crucial role in promoting or hindering infill development through their zoning ordinances, land use plans, permitting processes, and incentives. They can streamline regulations and offer subsidies to encourage desirable infill projects.¹