The National Standard Plumbing Code™ (NSPC)
First published in 1933, the NSPC is designed to ensure the proper installation of plumbing systems, providing local and state governments, code administration bodies, and the industry with a modern code to protect health and promote safety. In 2017, IAPMO and the Plumbing-Heating-Cooling Contractors—National Association (PHCC) executed an agreement transferring ownership of the NSPC to IAPMO. The transfer encompasses all editions of the NSPC and ensures the code can progress for years to come.
The 2024 National Standard Plumbing Code–Illustrated provides the latest information about common materials, fixtures, devices and equipment systems used or installed in plumbing systems. The NSPC contains revisions that have been included to promote sustainable plumbing practices. This new edition is printed in the popular illustrated format, with comments and illustrations clearly shown as supplemental information. The illustrations and supplementary notes make it an indispensable training tool.
Significant changes to the 2024 NSPC include the following:
Code Development
To keep the code current and viable and with input from all interested parties, the NSPC Committee — comprised of licensed contractors, engineers, inspectors and manufacturers — reviews the code annually and updates it on a three-year cycle.
Deadline to Submit Proposed Changes
for 2027 National Standard Plumbing Code (NSPC) is Feb. 28
In order to facilitate the development of an updated National Standard Plumbing Code — Illustrated (NSPC), the IAPMO NSPC Committee requests proposed changes to the 2024 NSPC. All proposals are due by Feb. 28, 2025. Proposals accepted by the technical committee will appear in the 2027 NSPC. Read more...
Ordering
Purchase 2024 National Standard Plumbing Code
Purchase 2021 National Standard Plumbing Code
Purchase 2018 National Standard Plumbing Code
If you are ordering from New Jersey, please contact your state bookstore to order:
New Jersey: Phone (800) 652-7422 or email director@nj-phcc.org
Online Editions
Read 2024 National Standard Plumbing Code
Read 2021 National Standard Plumbing Code
Read 2018 National Standard Plumbing Code
Read 2015 National Standard Plumbing Code
Read 2021 NSPC-New Jersey Edition
Read 2018 NSPC-New Jersey Edition
Online IAPMO and ASSE Standards
Read IAPMO ANSI Standards
Read IAPMO Industry Standards
Read ASSE ANSI Standards
Errata
Download Errata to 2021 1st Printing
Download Errata to 2018 2nd Printing
Download Errata to 2018 1st Printing
Download Errata to 2015 1st Printing
Download Errata to 2021 NSPC-New Jersey 1st Printing
Download Errata to 2018 NSPC-New Jersey 1st Printing
NSPC Technical Committee
NSPC Policies and Procedures
NSPC Committee Application
Have a Question
Email us at nspc@iapmo.org
NSPC Interpretation Inquiries
Informal & Formal: Dan Cole, NSPC Secretary, dan.cole@iapmo.org