Remodel permits in New Jersey and Pennsylvania.

If your remodel moves or adds plumbing, wiring, gas lines or walls, plan on a permit, in both states. Swapping finishes in place can be different, and where the line falls depends on the state code and your town. When in doubt, the construction office will tell you.

• The construction official has 20 business days to approve or deny a complete permit application. A missed deadline counts as a denial for appeal purposes, not as an approval. Source: N.J.A.C. 5:23-2.16 (via Cornell LII)
• No construction permit is issued until the conditions of all “prior approvals” are met. Source: N.J.A.C. 5:23-2.16 (via Cornell LII)
• When a permit is referred to a town’s historic commission, the commission has 45 days to report. If it doesn’t, that counts as a report in favor of the permit. Source: N.J.S.A. 40:55D-111 (via Justia)
• Under N.J.A.C. 5:23-2.15(f), an addition or alteration to an owner-occupied one- or two-family home needs zoning approval in place before the construction plans are reviewed. Source: N.J.A.C. 5:23-2 (NJ DCA)
• Some smaller work counts as “minor work”: it still needs a permit, but it can start once the construction office has been notified, before the permit is issued. Source: N.J.A.C. 5:23-2 (NJ DCA)

• A residential building permit is decided within 15 business days, or the application is deemed approved. The limit is 5 business days if a design professional certifies the plans meet the code. Source: 34 Pa. Code § 403.63 (via Cornell LII)
• A permit becomes invalid if work doesn’t start within 180 days. Source: 34 Pa. Code § 403.63 (via Cornell LII)

Historic districts and local offices add their own steps, and they often come before the building permit. A few examples from towns we work in:

• Princeton has 21 historic districts, and any exterior change to a building in one generally needs review by the Office of Historic Preservation. Source: Town Topics, July 29 2026
• In New Hope’s Borough Historic District, a Certificate of Appropriateness is required before zoning or building permits for exterior changes, painting included. Source: New Hope: When to apply for a COA
• Langhorne Borough’s permit FAQ says an in-kind kitchen or bath remodel may not need a building permit, but moving plumbing or walls, adding light fixtures, or adding counter space or an island means it does. Source: Langhorne Borough: Permit FAQ
• In Middletown Township (Langhorne addresses), the permit fee doubles if work starts before the permit is issued. Source: Middletown: Apply for a Permit
• In Millburn’s historic districts (Short Hills), interior work doesn’t need a Certificate of Appropriateness; exterior changes seen from a public street do. Source: Millburn Code, Art. 8

Each town page lists that town’s own rules with sources, including Princeton, New Hope, Newtown and Doylestown.

Call (609) 874-0990 or send us the form. We come see the house, and your written scope, after the visit, says what permits the work needs.