When "Done" Doesn't Mean Ready: The Real Work of Commissioning

Alex Mathers P.E., CxA, NEBB CP 

Alex@GMCCx.com 

Most people think commissioning is about testing systems. After 20 years in the field, I can tell you it's mostly about something else entirely. It's about working between contractors, vendors, and customers to make sure what's "done" is actually complete and ready to be tested. 

That gap between "done" and "ready" is where commissioning lives or dies. 

The Project Schedule Game 

Every project I've worked on has a schedule that is very detailed in the beginning. Demo, framing, drywall, and rough-ins are very detailed, however once it gets to TAB, startup, and testing there is usually one line item that says “commissioning” and starts on a specific date. The problem is, schedules don't know what's happening in the field. They don’t know delays, lead times, issues, troubleshooting, repairs, and required fixes and replacement. Schedules show what should be happening, not what is happening.  

Readiness isn't a date on a schedule. It's a condition. A site visit tells the true condition of the space. If you aren't prepared, you can walk in expecting to start testing, but you'll find filters not installed, TAB not complete, actuators needing replacement, and a BAS that drops offline every few hours. The schedule said ready. Reality said otherwise. 

Meetings vs. The Field

What gets discussed in coordination meetings is not always what is happening in the field. You’re shocked, I know. 

In meetings, everyone reports progress. Mechanical is 95% complete. Controls programming is loaded. TAB is wrapping up next week. Everyone nods, the schedule gets updated, and the meeting ends. 

Then you walk the site. The 95% mechanical complete actually means three air handlers haven't been started. "Controls programming loaded" means the logic is in the controllers but nobody has verified it against the approved sequences. TAB wrapping up means they are waiting for ceiling tiles and doors to be installed. 

This isn't anyone lying. It's how construction reporting works. Optimism rolls uphill, and problems get smoothed over. CxA's job is to cut through that polish and report what's actually true. 

Clear Ownership Matters

Most testing failures don't happen because people don't know what to do. They happen because nobody knows whose job it is. When ownership is fuzzy, things fall through the cracks. When two trades both think it's the other's responsibility, nothing gets done. When everyone owns it, nobody owns it. 

Clear ownership between teams makes or breaks execution. The CxA often ends up being the person who forces those conversations. Not in a confrontational way, but with the simple question, "Who's doing this and when?" 

The Checklist Solves a Specific Problem

We developed a "Functional Testing Site Readiness Checklist" to address all three of these issues at once. It's not paperwork for the sake of paperwork. It's a tool that does three specific jobs. 

1. It defines what "ready" actually means. Instead of vague status updates, the checklist lists specific conditions that must be true: Permanent power stable; Sensors calibrated; All systems in auto with no overrides active. There's no room for interpretation. 

   
   

2. It forces field verification. A contractor can't honestly check the box that says "all control loops verified and tuned" without actually doing the work. The checklist creates a moment where field reality has to match the report. 

3. It assigns ownership. Each item belongs to a specific trade. The electrical contractor handles their items. Controls handles theirs. The checklist becomes a coordination tool that makes ownership visible. 

Here is our developed Readiness Checklist: 

Functional Testing Site Readiness Checklist

General Notes

• Complete and permanent identification/labeling of all systems and components 

• Pre-functional checklists and pre-testing complete 

• Clear, safe access to all equipment 

• Pencils down, hands-off readiness: 48 hours of continuous automatic operation with no manual intervention, overrides, or alarms 

Electrical & Lighting Systems

• Permanent power stable and panels complete 

• Electrical acceptance testing complete 

• Motor starters and overloads set and tested 

• Lighting controls and emergency lighting complete 

Mechanical Systems 

• Equipment startup and manufacturer reports complete 

• VFDs programmed and locally tested 

• Final filters and strainers installed 

• Dampers and actuators stroked full travel 

Plumbing & Hydronic Systems 

• Domestic and process water supplies connected and tested 

• Hydronic systems flushed, filled, and balanced 

• DHW/IHW circulation and temperature verified 

Test and Balance 

• TAB substantially complete with report submitted 

• Ventilation rates verified at design conditions 

Controls & Automation 

• Field devices installed with point-to-point checkout complete 

• Sensors calibrated to design values 

• Control loop checks complete 

• Graphics and programming loaded and verified 

• BAS network stable with integration complete 

• SkySpark integration complete 

• All systems in auto with no overrides or bypasses active 

Safety Systems 

• All equipment safeties tested 

• All life-safety interlocks tested 

AHJ Sign-offs 

• Final electrical inspection signed off by AHJ 

• Final mechanical inspection signed off by AHJ 

• Fire alarm testing complete and signed off by AHJ 

• Fire sprinkler/suppression testing complete and signed off by AHJ 

What I've Learned

A site can look ready. Equipment is installed. Lights are on. Air is moving. People are working. But looks are deceiving. When the details are right, functional testing goes smoothly. When they're not, you spend your testing time troubleshooting installation problems instead of verifying performance. That's expensive for everyone. 

The Bottom Line

The CxA role isn't glamorous. A lot of it is asking uncomfortable questions. It's prioritizing real-world constraints over schedule optimism. It's filling in the gaps and getting alignment when things don't line up as cleanly as the project manager hoped. 

A good readiness checklist makes that work easier. It gives everyone a shared definition of done. It creates accountability without requiring confrontation. And it shifts the conversation from "Are we ready?" to "What specifically isn't ready and who's fixing it?" 

That's a much more useful conversation. And it's the only way to start functional testing without wasting everyone's time. 

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References and Further Reading:

• ASHRAE Guideline 0. The Commissioning Process. American Society of Heating, Refrigerating and Air-Conditioning Engineers. 

• ASHRAE Guideline 1.1. HVAC&R Technical Requirements for the Commissioning Process. 

• ANSI/NEBB Standard S110-2019  

• BCxA Best Practices documents  

• ASHRAE Guideline 36 (sequences of operation)  

• NFPA 72 (fire alarm)  

• NETA ATS (electrical acceptance testing)  

• AABC or NEBB TAB Standards  

• ASHRAE Standard 188 (Legionella/water systems)