“Layton Consulting Fenestration Nerds” By Anton Van Dyk: NAFS in Part 5 of the 2020 NBC - What does the “scope of the standard” (NAFS) cover?

Code changes are inevitable but changes like this one start to change what we are comfortable doing.  So, when a change happens, I spend time contemplating the change for what it means and what to do about it.  Words are words, but we have to figure out how to put these words into action.

The change to how NAFS is used in Part 5 is significant and will impact manufacturers who have used this path for compliance.  When you read the language, it refers to “not covered/are covered in the scope of the standard”.  It’s the term “scope of the standard” that is what made me think a bit deeper.

The issue is that, in the NAFS standard, products are listed as “not intended to be tested to this standard”.  But when the code uses the language “not covered/covered in the scope of the standard”, it would imply that the code language does not imply that it is about the products listed, but about what the standard requires you to do.

So, let's explore the “scope of the standard (NAFS) for structural loads.  For the most part, it addresses environmental loads, such as wind load; while the codes require windows in certain locations to meet guard loads and in some regions - seismic loads.

So based on this, any window that is required to meet loads that are not listed in the scope of the standard, would therefore result in a product that is “not covered” under the scope of the standard. 

The other code update for Part 9 buildings now requires a restrictor to be applied to a window that is operable below 900mm from the finished floor.  Based on this change some might now interpret any part of a window below 900mm is to meet guard load when the difference in floor levels is 600mm and greater as Part 4.1.5.16 requires walls to meet guard load and many then will say that a window in a wall needs to meet this. 

This is a tricky place to be when it comes to how to apply these code changes.  The important part is anyone in the window/door business, needs to have a strategy in place for their teams to know how to apply these changes to their methods.  The key is to not do this alone and to use the language that is provided in the code and the NAFS standard. 

I don’t know that this was the intent with this code change for NAFS in Part 5, but as the code language does not match the NAFS standard language, it has created some confusion and with confusion comes variable code interpretation. 

If you struggle with the code and do not know how to manage it in your business, I help manufacturers/installers proactively build compliance strategies.  Feel free to reach out to me to discuss this further. 

Shoot me an email at anton@laytonconsulting.com or call at 778-908-2811.