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Subjects › Planning › Zero Lot Line Development
Updated 06/2011

Zero Lot Line Development

Introduction

Zero lot line development involves the placement of a house on a lot so that one wall is on the property boundary. It is a technique that is used in small lot housing developments to preserve some of the privacy and yard space that is characteristic of single-family dwellings and to enhance their aesthetic appeal. The use of conventional zoning provisions which require that the home must be set back from every lot line is not always practical for small lots since the "yards" created on each side of the house are generally very small. Typically, zero lot line houses are sited on the same one side lot line. Placing the house on one of the side lot lines doubles the amount of usable space on the other side. For illustrations, see Image Examples below.

Some jurisdictions also include townhouse or condominium development as zero lot line development where the lot line falls between the units that are for sale. In this case, both sides of the unit fall on the lot lines. Other variations on the original zero lot line concept include the "angled Z-lot," "zipper lots," and "alternate width lots." The angled Z-lot turns the home at a 45-degree angle to the street, which enhances visual appeal and makes it possible to add more windows without compromising privacy. Zipper lots vary the depths of rear lot lines; this concentrates open space on one side of the lot, making wider lots possible with only garages located on the property line.

Zero Lot Line Code Examples - Washington Cities and Counties

General Information on Zero Lot Line Development

  • "Zero Lot Line Development," from Affordable Housing Techniques: A Primer for Local Government, MRSC, 1992
  • Portland, OR Zoning Code Ch. 33.405 - Alternative Design Density Overlay Zone and Ch. 33.110 - Alternative Development Options (Scroll to Section 33.110.240(I))

Zero Lot Line Image Examples