Australia, we need to talk about your specification of FRLs...

Firstly lets start by clarifying what exactly is an FRL?... Well it is a commonly used term, and in fact an acronym of "Fire Resistance Level". Which is defined in many places including the National Construction Code (NCC) and Australia Standard 1530.4 (AS1530.4).

The definition of FRL from the NCC is as follows with note attached. There is no other acceptable way to express FRLs.

"Fire-resistance level (FRL) means the grading periods in minutes determined in accordance with Schedule 5, for the following criteria-

(a) structural adequacy; and

(b) integrity; and

(c) insulation,

and expressed in that order."

If you want to know more about what these all mean jump, across to the link below which sets it all out in more detail.

Anyway lets continue. As someone who deals with needing to specify systems to meet a given performance, far too often I see the following on drawings, specifications or requests: 2hr, 120min or 120 fire rating. Does this mean 120/-/-, -/120/-, -/120/120 or 120/120/120?

This is problematic in many ways, as many building elements have varying performance needs. Whether they be loadbearing, non-loadbearing or integrity only etc. Some elements may even have varying FRLs for the element, such as 120/90/60, so great confusion abounds if we don't get the full picture.

As a consultant and manufacturer how are we to know what performance solutions are being use on the project, what concessions the BCA consultant has allowed for, and many more variables. We more often than not, have to go back and ask a series of questions, only to find out the clients themselves don't even know. Then the fun and games begin to get to a final conclusion of what performance is actually needed.

In closing please ensure when doing your fire rating plans, you use full FRLs, expressed in the properly defined manner. It will save any confusion or headaches further down the project track.

Look forward to seeing beautifully specified FRL's into the future now.