Mountainside Borough

Union County

Text Client checklist

Certificate of Occupancy

Not required

Phone: 908-232-2919

Official page

Smoke and CO alarm certificate

Required

Requirements

Smoke alarm on each level and outside each separate sleeping area
Battery-only smoke alarms must be 10-year sealed battery units (listed to ANSI/UL 217); hardwired alarms from original construction or rehabilitation may not be replaced with battery alarms
Carbon monoxide alarm in the immediate vicinity of the sleeping areas (battery, hardwired or plug-in)
Portable fire extinguisher within 10 feet of the kitchen, listed and labeled, rated at least 2A-10B:C and no more than 10 pounds (still listed on the Borough page as of October 2026, although the state dropped it from the sale certificate in February 2025)

Borough of Mountainside Construction Department, Smoke Detector Re-Sale Certification (fire code enforcing agency: Scotch Plains Township under a shared service)

Fees

Smoke detector, carbon monoxide alarm and portable fire extinguisher re-sale certification (residential)

$100.00

Timing

After the fee is paid and the online form is submitted, the Borough sends an inspection date. Inspections are Tuesday 3 to 6 pm and Thursday 1:30 to 4:30 pm.

Phone

908-232-2919

Official page

Last checked October 2, 2026

Sources

https://www.mountainside-nj.com/department/buildingzoningengineering/

Other towns in Union County

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