Parsippany-Troy Hills, NJ Accessory Structures: Garage Conversions (2026)

Section 430-50E of the Parsippany-Troy Hills Township Code is the garage conversion rule for the R-1 District. It lists affordable accessory apartments as a conditional use in the R-1 District only, and subsection (3) says that construction of an addition or conversion of an attached garage is permissible, so long as adequate off-street parking for both the principal residential use and the apartment is provided. The definition in § 430-8 describes the unit as created through the conversion of an existing attached accessory structure on the same site, or by an addition, and occupied by a low- or moderate-income household.

The lot must be at least 40,000 square feet with a width of at least 200 feet. The apartment needs its own separate entrance from ground level, not visible from the street, and it cannot be accessible from the principal building. The floor area of a newly constructed or converted unit cannot be less than 450 square feet or more than 750 square feet, and no more than two persons can occupy it. Only one principal single-family residence and one accessory apartment can sit on a lot, and every accessory apartment must provide at least one off-street car parking space.

The unit has to be approved under the Township's accessory apartment program to be rented to a low- or moderate-income household. Before a building permit issues, a new deed restriction must be recorded in the Morris County Clerk's Office stating the apartment will be maintained as affordable for at least 30 years. The dwelling structure must comply with the Uniform Construction Code and Uniform Fire Code requirements to the extent required by the Construction Official. If the unit is not serviced by the Township sewer system, approval of the Morris County must be obtained before Planning Board approval.

The program is capped. No more than five moderate-income affordable accessory apartments are permitted within the Township, and the provisions become null and void on issuance of a building permit for the 10th affordable accessory apartment, provided at least half of those units are rented to a low-income household.