Delaware (DE) Plumbing Code & Permit Rules
International Plumbing Code (2021)
Data: State plumbing boards, ICC, IAPMO, EPA
Our reference data lists Delaware as requiring licensed plumbers for most plumbing work; testing of backflow prevention assemblies may be required under state or local rules. These regulations help protect water quality but mean higher costs for homeowners compared to states that allow DIY work.
Plumbing Code
Delaware follows the International Plumbing Code (2021 edition).
Key Regulations
| Regulation | Status | Details |
|---|---|---|
| Plumbing Code | IPC (2021) | International Plumbing Code |
| Homeowner DIY | Not allowed | Licensed plumber required |
| Water Heater Permit | Required | |
| Backflow Testing | Annual, required | |
| Seismic Strapping | Not required | Water heater restraint |
DIY Plumbing in Delaware
Delaware requires a licensed plumber for most plumbing work. Licensed plumber required
While this increases costs, it ensures:
- Work meets current code requirements
- Proper permitting and inspection
- Warranty and liability protection
- Safe connections to water and sewer systems
Backflow Prevention
Delaware requires annual backflow testing to protect the public water supply from contamination. Testing must be performed by a Certified tester.
Non-compliance penalty: Water service may be shut off if testing is not completed on schedule.
Water Conservation Requirements
Delaware follows federal water conservation standards. Federal minimums apply
Lead Service Line Replacement
Delaware is subject to EPA lead service line inventory and replacement requirements.
Data Sources
- Delaware state plumbing board and licensing agency
- International Code Council (ICC)
- IAPMO
- EPA Safe Drinking Water Act
Updated as regulations change.
Need a licensed plumber in Delaware?
Plumbing regulations vary by city. Connect with a licensed professional who knows your local code requirements.
Find a Licensed Plumber →Frequently Asked Questions
What plumbing code does Delaware follow?
Delaware follows the International Plumbing Code (2021 edition) as of our last review; state and local amendments may apply.
Can I do my own plumbing work in Delaware?
Our reference data lists Delaware as requiring a licensed plumber for most plumbing work; homeowner exemptions may apply, so check state and local permit rules.
Do I need a permit to replace a water heater in Delaware?
Permit rules for water heater replacement in Delaware depend on the state and your local jurisdiction; check with your local building department. Check whether state and local rules require a licensed plumber for the installation.
Is backflow testing required in Delaware?
Backflow testing requirements in Delaware depend on the state code and your water utility; check with your utility about which assemblies must be tested and how often.
Does Delaware require seismic strapping for water heaters?
We have no statewide seismic strapping requirement for water heaters on record for Delaware; local building codes may still require it, so check with your local building department. Strapping remains a prudent option in areas with seismic activity.