New Hampshire (NH) Plumbing Code & Permit Rules
International Plumbing Code (2018) · Updated 2026-05-31
Data: State plumbing boards, ICC, IAPMO, EPA Last verified: 2026-05-31
New Hampshire requires licensed plumbers for most plumbing work and mandates annual backflow testing. These regulations help protect water quality but mean higher costs for homeowners compared to states that allow DIY work.
Plumbing Code
New Hampshire follows the International Plumbing Code (2018 edition).
Key Regulations
| Regulation | Status | Details |
|---|---|---|
| Plumbing Code | IPC (2018) | 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 New Hampshire
New Hampshire 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
New Hampshire 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
New Hampshire follows federal water conservation standards. Federal minimums apply
Lead Service Line Replacement
New Hampshire has an active lead service line replacement program. Following EPA Lead and Copper Rule 2021
Data Sources
- New Hampshire 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 New Hampshire?
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 New Hampshire follow?
New Hampshire follows the International Plumbing Code (2018 edition).
Can I do my own plumbing work in New Hampshire?
No, New Hampshire requires a licensed plumber for most plumbing work.
Do I need a permit to replace a water heater in New Hampshire?
Yes, New Hampshire requires a permit for water heater replacement. A licensed plumber is required for the installation.
Is backflow testing required in New Hampshire?
Yes, New Hampshire requires annual backflow testing.
Does New Hampshire require seismic strapping for water heaters?
No, New Hampshire does not require seismic strapping for water heaters. However, they remain a prudent option in areas with seismic activity.