In-fill Development

In-fill development is the process of providing a viable use of vacant or underused properties in areas that are already largely developed. Nearly all municipalities contain some degree of vacant or underused lands, which may have resulted over time for a variety of reasons including irregular lot shape, difficult access, inadequate infrastructure, environmental contamination, natural or historic resources considerations, or economic issues, among others. These sites can vary in form and size and the reasons for their past underuse may still be a challenging factor.

In-fill sites are commonly found in the form of smaller scattered parcels of land that were bypassed by earlier development, were once occupied by buildings, or still contain decayed abandoned structures. When several of these small parcels border each other, they can be developed in conjunction with one another or incorporated into larger sites. Potential in-fill sites are also found in underused parcels that can accommodate additional development or larger parcels that could be further subdivided. A key element that distinguishes in-fill from other types of development is the utter importance of the compatibility of the new building design and placement with the surrounding buildings, context, and neighborhood.

In-fill development accommodates growth using a concentrated pattern that consumes less land and resources, and directs development to appropriate areas. In-fill development can also serve community goals for reduced traffic congestion, maximum use of existing infrastructure, supporting alternate transit options, sustainable development/energy conservation, and opportunities for diversity in housing.


The following benefits are associated with in-fill development:

In-fill Development


The following are potential difficulties to implementing in-fill developments:


The following discussion provides a generalized planning approach for municipalities interested in encouraging and creating a favorable climate for infill development. First, policy considerations are outlined, followed by a discussion about local regulations.

Policy Formulation

A broad vision or policy that supports in-fill development should be established in the municipal comprehensive plan or economic development plan. This can take the form of a goal or objective. Types of appropriate land uses and areas for in-fill should be identified during the planning process and included in the plan. For example, a town center is an appropriate area in which to target in-fill development, as well as redevelopment, and developing a concept plan or design guidelines could be included as plan recommendations. In-fill development should be included as a plan implementation action with strategies outlining how such development will be encouraged and implemented. Planning analysis and recommendations could also occur at the neighborhood level with discussion, for example, about in-fill on a micro-level and specific planning issues such as compatibility of land uses. Encouraging cooperative efforts among interested parties is also an important policy consideration in creating a climate conducive to infill.

Inventory of Potential Infill Sites

An inventory of vacant parcels and underused sites should be undertaken to determine the existence and location of possible sites for in-fill development. There should be consideration of ownership, availability, condition, encumbrances, as well as zoning and other regulatory measures that may affect development of a site. Once an inventory is completed, sites where in-fill development would be most successful and appropriate should be analyzed and prioritized.

Growth Boundaries

Growth boundaries can be established to focus development in certain areas of a municipality, thereby directing where and how growth should occur. In this way, development of open lands and resources can be limited and growth guided to designated areas where in-fill and compact land use patterns are most appropriate.

Design Considerations

Creating guidelines for infill design can help alleviate community concerns about its compatibility. Their purpose is to ensure new in-fill development relates to the larger community context and fits within the existing character. Design guidelines should take into account characteristics of existing structures/sites, development/block patterns, and context, and more specifically should address site design (e.g. the relationship between buildings and streets), streetscaping and landscaping (e.g. walkways, signage, common areas, and street trees), and building design (e.g. massing, proportion, scale, rhythm, and material). Guidelines should promote new buildings that reflect rather than imitate existing structures. The process of developing guidelines offers a good opportunity for community involvement, and to clarify the design features most important to the community so these valued qualities can be incorporated into in-fill development.

Design guidelines are voluntary, offering suggestions about the types of design the community feels is most compatible. Use of guidelines may also be linked to incentives, such as eligibility for grants or financial assistance, while certain design elements may be required via regulation, such as yard setbacks, parking design standards, or in a locally regulated historic district where building design can be addressed. Design issues will vary within each of Chester County's landscapes.

Local Regulations Conducive to In-fill Development

Municipalities can adopt provisions to help implement in-fill policy. They should review ordinances and codes to determine if any provisions preclude infill development and ways these barriers can be overcome. Likewise, regulations should be examined to determine where ordinance incentives for in-fill development are in place or could be added.

Issues to Consider

In addition to setting planning policy and addressing land use regulations, municipalities can take other measures to make in-fill development more feasible and encourage its development. The following are possible actions that can be employed along with policy and regulatory measures to promote in-fill development. These actions involve both indirect and direct strategies.

Community Support and Involvement

A primary barrier to infill can be community opposition. It may be due to concerns about poor quality or incompatible design, overcrowding of facilities, and increased traffic congestion. Community resistance can serve as a major disincentive to developers. Unlike development of greenfields, in-fill sites are located in established municipalities, and thus community involvement in specific projects and overall community acceptance of in-fill is key to project success. Design guidelines (discussed above) are one method that can help address and mitigate these concerns, and community participation should be incorporated into the design guideline process.

Community involvement in the establishment of long-range planning policy can diminish later conflicts, as well as establish a basis for trust between the community and local government necessary for municipal advancement of and incentives for in-fill development. Municipalities can provide educational information about public benefits of in-fill and compact development, as well as well-defined policies and regulations that reflect community sentiment. Serving as a liaison and helping to mitigate conflicts that may arise between developers and community organizations as well as working collaboratively with interested groups are two additional roles a municipality can play to facilitate in-fill projects.

Infrastructure Improvements and Provision of Public Facilities and Services

Municipalities can invest in infrastructure improvements and provide public facilities and services in target areas to increase the attractiveness of in-fill development. They may invest directly in improvements or can strategically locate facilities and services to attract outside investment. Existing facilities, services, or infrastructure may be inadequate. For example, undersized or deteriorated piping or lack of direct road access can inadvertently serve as disincentives for new in-fill projects. Where these types of limitations exist, municipalities can provide public investment to improve the existing system. By targeting improvements, municipalities can benefit from the cost savings of containing development within the existing service area and using compact development patterns. These savings are realized because of long-term lower costs of providing infrastructure and facilities within a concentrated area, rather than to an extended network.

Through capital improvement programming and budgeting, municipalities can provide for necessary infrastructure and public facilities improvements. Improvements can include site-specific upgrades and construction of new facilities, such as a community center, in target areas. On a broader scale, improvements can be part of a development plan for a larger land area, such as town center revitalization. Facilities and infrastructure improvements may involve sewage service upgrades, roadway capacity, or streetscape and parking improvements, while services such as maintenance of vacant parcels, code enforcement, blighted, abandoned building demolition, and road repair can help enhance an area and improve its attractiveness for investment and development.

In-fill Development

Project Financial Assistance

Since higher financial risk can be associated with in-fill development and overall costs may be greater, municipalities can offer financial incentives to help spur infill development. Assistance can take the form of direct funding, assumption of loan interest payments, obtaining grants, loan guarantees or letters of credit, or encouraging lenders to provide loans or furnish low interest rates. Other strategies include tax or fee reduction, tax-exempt bonds, technical assistance, project endorsement, land banking, and land acquisition, or exchange of parcels for in-fill projects. Sharing or undertaking infrastructure or site improvements, parking, or site remediation are other methods of providing financial assistance. Financial assistance can apply to various elements of project costs, including feasibility analyses, demolition or site clean-up, or construction, dependent on the nature of the project and assistance required.

Municipal Assistance

Municipalities can provide varying forms of assistance to help offset costs and facilitate project initiation and completion. For example, they may lease space in infill developments, purchase goods from infill businesses, assist with funding/grant applications, facilitate public outreach, interface with other parties for technical assistance, work with lending sources to promote funding for in-fill development, create regulatory incentives or a climate conducive for infill, or share market and other information for in-fill studies.

Additionally, a current inventory of vacant parcels featuring key sites can be available as a way of advertising appropriate sites for in-fill development. This allows developers to be aware of a municipality's support and proactive role in infill and gain needed information about possible sites. This also allows municipalities to have a forum to provide information about assistance available in undertaking in-fill projects, such as potential partnership opportunities.

Site Contamination Mitigation

Possible risk of and actual environmental contamination issues are another obstacle for in-fill projects on former commercial and industrial sites. Municipalities can address this issue by informing developers about sites that have potential contaminants, helping facilitate site remediation, or providing information about state programs such as PA Land Recycling Program.

Checklist for Successful In-fill Development

The following general guidelines serve as a checklist to stimulate successful in-fill project, recognizing that factors other than zoning are important for successful infill. Local governments can:

Legal Basis

Examples In-fill Development

Zoning provisions for in-fill development are included in the West Chester Borough Zoning Ordinance, as follows:

Related References

Publications addressing smart in-fill development include:

Related Tools

Landscapes2 Relevance

In-fill development is specifically supported by Landscapes2 as LU Policy LU 3.1— "Support infill development and redevelopment efforts, consistent with the existing neighborhood character, based upon infrastructure capacity and environmental constraints."