Before You Build in Mahwah, NJ: Permit & Rule Checklist (2026)

Mahwah caps accessory retaining walls behind the front facade at 6 feet and requires construction permits with engineering for taller residential walls.

Mahwah Township limits fences to 4 feet in front yards and 6 feet in side and rear yards under Chapter 24 zoning rules.

Mahwah requires a zoning permit application for all new and replacement fences before installation begins anywhere in the township.

Mahwah enforces fencing requirements around private pools, requiring barriers at least four feet tall with self-closing, self-latching gates as part of zoning compliance and the New Jersey state pool code.

Mahwah requires zoning and construction permits before installing private residential swimming pools, with site plans showing setbacks, fencing, and equipment locations submitted to the Township for approval.

Mahwah permits accessory apartments as a conditional accessory use in all residential zones under Chapter 24 (Zoning) of the Township Code. Section 24-4.1(d) authorizes the use, while Section 24-6.1(j) sets the conditions: one accessory apartment per single-family residence, 400 to 800 square feet, no more than 30% of the habitable living space, a maximum of three occupants, and the principal building must be owner-occupied at all times. After July 1, 1997, no new affordable accessory apartments may be created.

Mahwah Township's zoning code regulates residential sheds by size, with smaller utility sheds allowed close to property lines and larger accessory structures held to stricter setbacks and height limits.

Mahwah allows recreational fires in approved devices but requires a 25-foot clearance from structures, constant attendance, and on-site fire-extinguishing equipment under the Bureau of Fire Prevention rules.

Mahwah prohibits open burning on public property and requires a permit from the Bureau of Fire Prevention for bonfires, with leaf, rubbish, and waste vegetation burning banned outright.

Mahwah requires a permit at least 15 business days before removing regulated trees, with replacement at equal or greater diameter required.

Mahwah restricts outdoor watering from May through September, prohibiting Sunday watering and enforcing odd/even address day rules.

Mahwah reserves authority to plant, prune, and maintain trees within public rights-of-way, while permitting non-harmful pruning on private property without a permit.