HIP Tool: Infill Development

Infill development refers to any new development in already built-up areas. It can also mean redeveloping existing properties to make more efficient use of the land. Generally, infill increases neighborhood density and the ratio of improvement-to-land value of the property.


Infill development adds residential capacity to cities without annexation or infringing on open space or other sensitive areas. Instead, it directs development to areas where it already exists. This can be a cost-effective strategy for cities and developers. Directing growth to already-serviced neighborhoods avoids the cost of sewer, road and other utility extensions. Infill development can help achieve goals like creating transit-oriented development and increasing neighborhood density and diversity.

Infill development generally occurs on individual properties or a collection of neighboring properties. Cities can encourage infill development by aggregating neighboring properties into larger parcels for (re)development. Properties that make good candidates for infill development are those served by transit and other amenities. They are located in densely zoned neighborhoods or neighborhoods built below their zoned density, are vacant or economically underutilized, or are large enough to be subdivided.

Despite the numerous benefits of infill development, barriers to its widespread application exist. Infill construction can be inhibited by neighbors’ concerns about increased density or different housing types, by infrastructure in need of modernization and by regulatory barriers preventing innovative forms of housing. Coupling infill development strategies with other tools may help overcome these problems. Creating overlay zones and flexible development regulations can help remove regulatory barriers for smaller or oddly sized lots. A lot size averaging ordinance could be implemented in neighborhoods where vacant lots are smaller than the minimum requirements. Jurisdictions can encourage infill by offering density bonuses or using incentive zoning, especially for development incorporating affordable housing. Applying design guidelines to infill projects and conducting citizen outreach can help ease community concerns about density and character of development.

Tool Profile

Focus Areas

  • Expensive Housing Markets
  • Innovative Single Family Techniques
  • Urban Centers

Project Types

  • Single Family
  • Multifamily
  • Ownership
  • Rental
  • Market Rate
  • Subsidized

Affordability Level

  • 80 to 120% AMI
  • Less than 80% AMI

Housing Goal

  • Diversity