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Middle Housing Land Divisions

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Source: Middle Housing Land Divisions ↗ Last modified: Sun, 19 Apr 2026 20:03:58 GMT

A middle housing land division (MHLD) allows you to divide a property into separate lots when developing certain housing types. This process is faster and has fewer approval requirements than a standard land division.

What is a middle housing land division (MHLD)?

Example of a Middle Housing Land Division (MHLD) project dividing a fourplex into four lots.

An MHLD allows a property with qualifying housing to be divided into separate lots so each lot can be sold individually.

MHLD applies only to certain types of residential housing.

Does my project qualify?

Middle Housing Land Divisions (MHLDs) apply only to certain types of residential development.

Housing types that qualify for MHLD

  • Duplexes
  • Triplexes
  • Fourplexes
  • Cottage clusters

The qualifying housing must exist or be proposed as part of your project.

Duplex

Two attached units on one lot before dividing.

For division eligibility, units must share a common wall (not floor or ceiling).

Detached duplex (in single-dwelling zones)

Allowed when:

  • The existing house is at least five years old
  • The new unit is no taller than 25 feet
  • The site is not within the Constrained Sites "z" overlay

Triplex or Fourplex

Three or four attached units on one lot before dividing.

For division eligibility, each unit must share a common wall (not floor or ceiling).

Cottage cluster

Three to 16 detached dwelling units oriented around shared common space (on one lot before dividing).

Cottage clusters:

  • Minimum site size requirements depends on zone
    • Allowed in the following zones:
      • RM1, R2.5, and R5: minimum site size of 5,000 square feet
      • R7 and R10: minimum site size of 7,000 square feet
  • Maximum site size: one acre
  • Must keep common outdoor space clear of projections such as eaves, overhangs, porches, bay windows, stairs, stoops, decks, mechanical equipment, or individual patios

Not allowed for MHLD

  • Creating vacant lots for future development
  • Buildings constructed under the commercial building code or other non-residential development
  • Projects with more than one home per lot (such as a house with an ADU)
  • Detached houses, unless they qualify as a detached duplex or cottage cluster

This list is not exhaustive.

Key rules of MHLD

With a middle housing land division:

  • Each lot can have only one dwelling unit (home), regardless of the zone. Accessory dwelling units (ADUs) are not allowed.
  • Lots created through an MHLD cannot be divided again in the future.
  • New lots don't have to meet minimum lot size or street frontage requirements.
  • The housing type stays the same after the land division. For example, a triplex remains a triplex for zoning purposes.
  • Zoning development standards still apply to the original site even after the land division is complete.