Delaware plumbing code: which edition applies and what it requires

Does Delaware use the IPC or the UPC?

Delaware uses the IPC. Its plumbing code is based on the International Plumbing Code published by the ICC, not the Uniform Plumbing Code.

The adopted code is the State of Delaware Plumbing Code = 2021 IPC with DE amendments (16 Del Admin Code 4455). It takes the IPC as its base and may layer state amendments on top, so a cited section refers to the state-adopted edition with the IPC as the underlying model.

What edition of the plumbing code does Delaware use, and when did it take effect?

Delaware's current edition is 2021 IPC, effective 2022-08-01, adopted by the Delaware Division of Public Health (DPH), DHSS.

Codes update on a multi-year cycle, and an adopted-but-not-yet-effective edition can circulate near a changeover. Confirm which edition your project falls under by its permit date and your local jurisdiction.

How do local jurisdictions affect Delaware's plumbing code?

Delaware's code is the statewide baseline, but local jurisdictions enforce it and may add amendments. The local authority having jurisdiction (AHJ) resolves how it applies to a specific project.

Statewide DPH-adopted IPC enforced by all political subdivisions; building codes stay county home-rule. Confirm any local amendments and the accepted trap-seal methods with your city or county building department before relying on a provision.

What does the plumbing code require for floor drains and trap seals?

Floor drains rely on a trap, and the code requires that trap seal to be maintained. A floor drain that receives little water can lose its seal to evaporation, which opens a path for sewer gas, odors, and pests.

To prevent that, codes recognize trap seal protection methods. The two most common are a trap seal primer (which adds water to the trap) and a barrier-type floor drain trap seal protection device (which provides a mechanical seal). The right approach depends on the drain, the space, and the AHJ.

In Delaware, that requirement sits in the traps chapter of the adopted code (Chapter 10). The IPC lists a barrier-type floor drain trap seal protection device conforming to ASSE 1072 as an accepted method under Section 1002.4.1, alongside trap primers and deeper-seal traps.

Are barrier-type (ASSE 1072) trap seals allowed under Delaware's code?

Yes. The IPC lists a barrier-type floor drain trap seal protection device (conforming to ASSE 1072) as one of the methods for protecting a floor-drain trap seal from evaporation, alongside trap primers (IPC 1002.4.1.4).

ASSE 1072 is the standard titled "Performance Requirements for Barrier Type Floor Drain Trap Seal Protection Devices." Because it is a co-equal listed method, a barrier-type device can be used in place of a trap primer where a floor-drain trap is subject to evaporation. Acceptance for a specific project rests with the AHJ.

Do I need a permit to add a floor-drain trap seal in Delaware?

Usually not for the device itself, but always confirm with your local authority having jurisdiction.

A drop-in barrier-type trap seal device generally does not require a plumbing permit because it does not alter any piping, similar to changing a drain grate. On new construction or an already-permitted renovation, include it in the plumbing specifications.

In Delaware, plumbing permits and inspections run through Delaware Division of Public Health and the local building department, and a licensed plumber pulls permits for plumbing work. Licensing rules and reciprocity vary, so confirm them with the authority or your local jurisdiction.

Where can I read Delaware's plumbing code?

The adopting authority and code text are linked below. Always confirm current requirements against the adopted code and your local AHJ.

• dhss.delaware.gov/dph/hsp/plumbing.html
• regulations.delaware.gov/AdminCode/title16/4455
• www.law.cornell.edu/regulations/delaware/16-Del-...