Canadian plumbing code changes 2025

🛠 National Plumbing Code of Canada 2020: What’s New in the 2025 Revisions

 

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The 2025 Revisions and Errata Package for the National Plumbing Code of Canada 2020 introduces important updates to improve accuracy, clarify requirements, and align with evolving industry practices. These updates come into effect as part of the ongoing effort to support consistency and safety in plumbing system design and installation across Canada.

 

🔧 Key Areas of Change:

1. Pipe Sizing and Fixture Unit Revisions

The 2025 update includes revised fixture unit values for water supply in Table A-2.6.3.1. These changes reflect updated water usage data and modern low-flow fixtures. As a result, pipe sizing guidance is now more aligned with real-world demand, helping prevent oversizing and stagnation.

🔹 What’s Changed:
Fixture unit values and demand factors in Table A-2.6.3.1 have been updated to reflect current usage patterns and improve water system efficiency.

 

2. Expanded Guidance on Backflow Prevention

To strengthen potable water protection, the new revisions provide clarified language regarding CSA B64.10-compliant devices and their required locations in both residential and commercial applications.

🔹 What’s Changed:
Revised wording in Sentence 2.6.2.6.(1) now requires the use of backflow preventers at all cross-connections, including hose bibs and irrigation systems, in accordance with CSA B64.10.

 

3. Drainage and Venting Clarifications

The revisions also clarify minimum slopes for horizontal drainage piping and improve guidance for vent sizing in complex wet venting layouts.

🔹 What’s Changed:
Sentence 2.4.8.1.(2) has been updated to specify that horizontal pipes ≤ 3" in diameter must maintain a minimum slope of 1:50 (2%), and ≥ 4" pipes a minimum of 1:100 (1%).

 

4. Updates to Material Standards

New references to CSA B137 and ASTM updates have been incorporated to reflect the latest performance and safety standards for piping materials like PEX, CPVC, and copper.

🔹 What’s Changed:
Table 2.2.5 updates references to CSA B137.1, B137.3, and ASTM B88 to reflect their latest editions.

 

5. Errata Corrections and Wording Adjustments

Several minor corrections address typographical errors, cross-references, and ambiguous wording found in the original 2020 publication.

🔹 What’s Changed:
Cross-references between subsections in Division B were corrected for consistency, and several footnotes were clarified to improve interpretation.

 

 

✅ Why This Matters

The 2025 revisions are essential for:

• Ensuring compliance with the latest CSA standards
• Designing more efficient, right-sized plumbing systems
• Preventing costly errors due to outdated or unclear code language
• Supporting better environmental and public health outcomes through improved backflow protection and water conservation

 

 

 

📘 Reference:

Document: NPC 2020 Revisions and Errata Package (Effective February 2025)
Publisher: National Research Council Canada

Link: Download via NRC (or link to your hosted PDF)