Wilmington, DE Building Safety: Plumbing Permits (2026)
Key Facts
- Code adopted
- International Plumbing Code, 2018 Edition
- Permit fee
- $20, added to building permit
- Permit expires
- 90 days if work unstarted
- Homeowner exemption
- Owner-occupied single-family, no gas work
- Enforced by
- Dept. of Licenses and Inspections
Summary
Wilmington requires a permit from the Department of Licenses and Inspections before starting plumbing work, with a narrow exception for faucet or valve repairs; new piping or fixture additions always need one.
Plumbing work shall not be commenced until a permit for such work has been issued by the Department of Licenses and Inspections. A permit is not required for repairs which involve only the working parts of a faucet or valve. New piping additions to an existing piping system and the addition of any fixtures will require a permit. Plumbing work as described above, that does not require a permit, and does not have to be done by a licensed plumber, shall be done in accordance with all Code standards and subject to inspection by the plumbing inspector(s) at any time.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Code of Ordinances: Supplement 72).
Full Breakdown
Wilmington adopted the 2018 International Plumbing Code as its plumbing code (City Code § 4-126) and locally amended its permit section. Under the amendment, plumbing work cannot begin until the Department of Licenses and Inspections issues a permit; only repairs to the working parts of a faucet or valve are exempt, while new piping additions or added fixtures always require one. Permits lapse if work doesn't start within 90 days or is abandoned for 45 days. A single-family owner-occupant may do their own plumbing work on that residence, but may not install gas appliances themselves, and licensed master plumbers must carry liability insurance to be issued permits.
Violations & Fines
Unpermitted or noncompliant plumbing work is a code violation: fines of $250-$1,000 for a first offense, up to $2,500 for a second, and $1,000-$5,000 for a third or later; corporations face fines up to $5,000; each day of continued violation is a separate offense.
Frequently Asked Questions
Do I need a permit to fix a leaky faucet in Wilmington?
Can a Wilmington homeowner do their own plumbing?
Sources & Official References
Other rules in Wilmington
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