December 30, 2025
Introduction
New construction projects move fast, and mechanical systems often represent one of the most complex and costly parts of the entire build. Yet many project teams wait too long to involve their commissioning and TAB contractor. The result is delayed schedules, costly rework, performance issues, and systems that never reach their intended efficiency.
Early involvement is the key to successful new construction commissioning. When your TAB partner joins during design and pre-construction, the entire project benefits. Airflow requirements are clarified early, coordination improves across all trades, documentation stays on track, and final occupancy becomes far more predictable.
This guide outlines a month-by-month commissioning timeline used on successful Florida projects, including optimal hiring timing, deliverables at each phase, and the financial risks of waiting too long.
1. Pre-Design Phase: The Ideal Time to Hire Your TAB Contractor
The most successful commissioning projects begin before construction documents are finalized. During the pre-design phase, the TAB team ensures that mechanical and control strategies are realistic, code-compliant, and aligned with project goals for comfort and energy performance.
Key Deliverables in This Phase
- Review of the owner’s project requirements and basis of design
- Early identification of airflow and ventilation needs
- Collaboration with design engineers to confirm realistic balancing strategies
- Initial commissioning plan and project scope outline
Why Early Hiring Matters
Involving your TAB contractor at this stage prevents costly redesigns. Early validation of ventilation rates, zoning layouts, and mechanical capacity avoids many of the issues that otherwise show up late in construction. For Florida buildings with high humidity and cooling loads, early input is especially important.
2. Design Development Phase: Integrating Commissioning into Construction Documents
During design development, mechanical drawings, equipment schedules, and control sequences take shape. This is a critical point for your commissioning partner to provide technical guidance.
What the TAB Team Does
- Reviews drawings for balancing accessibility
- Confirms mechanical systems meet Florida building code requirements
- Provides recommendations for AHU sizing, VAV distribution, and control logic
- Ensures testing points, dampers, and valves are properly specified
Benefits of Involvement
Mechanical systems designed around realistic balancing requirements reduce static pressure issues, airflow deviations, and cost overruns. Projects that integrate TAB feedback at this point consistently achieve smoother commissioning later in the schedule.
3. Early Construction Phase: Site Coordination and Schedule Alignment
Once construction begins, trade coordination becomes essential. The TAB contractor needs to be looped in early so they can align with mechanical, controls, and electrical contractors.
Key Activities
- Site walkthroughs to confirm placement of diffusers, VAV boxes, and ductwork
- Verification that access panels and dampers are installed for proper testing
- Updates to the commissioning plan based on field conditions
- Coordination with the general contractor on milestone dates
Why Timing is Critical
If TAB requirements are not addressed during early construction, crews often need to revisit completed work later in the project. This increases cost and causes significant schedule delays.
4. Mid Construction Phase: Functional Infrastructure and Controls Integration
As mechanical systems are installed, the commissioning team evaluates component-level readiness. Controls integration becomes a primary focus.
TAB Deliverables During Mid-Construction
- Inspection of ductwork and equipment installation quality
- Verification of VAV box calibration points
- Confirmation of sensor placement and control wiring
- Preliminary airflow measurements to identify issues early
Florida Related Considerations
High humidity and cooling loads in Florida require careful control sequence validation. Improper control logic can lead to mold risks, excessive energy use, and tenant discomfort if not caught early.
5. Late Construction Phase: System Startup and Functional Testing Prep
Toward the end of construction, equipment startup and system integration begin. This is where the TAB contractor becomes central to the project timeline.
What Happens Here
- Equipment startup verification
- BAS point-to-point checks
- Preparation for full system balancing
- Creation of testing and commissioning checklists
- Coordination with mechanical contractors for issue resolution
Delays often occur when commissioning is brought in too late. Issues discovered at the end of the project are far more costly to correct.
6. Final TAB and Commissioning Phase: Testing, Documentation, and Verification
This is when systems are tested under real operating conditions to verify performance.
Primary Activities
- Complete HVAC system balancing
- Functional performance testing of all mechanical equipment
- Verification that ventilation and comfort requirements are met
- Delivery of the final TAB report and commissioning documentation
- Support during AHJ inspections and owner training
Impact on Occupancy
Accurate balancing and documentation ensure the project is ready for final inspections and occupancy approvals. This phase determines whether the building meets energy goals, code requirements, and design intent.
7. Post Occupancy Phase: Seasonal Performance Review and Warranty Validation
Commissioning continues after occupants move in. This phase ensures the building performs correctly during different load conditions.
TAB Responsibilities Post Occupancy
- Seasonal testing for cooling-dominant Florida conditions
- Review of occupant comfort and performance data
- Adjustment of ventilation and airflow based on real use
- Validation of equipment operation during the warranty period
This final step ensures the building maintains long-term reliability and efficiency.
Gantt Chart Style Timeline Overview
A simplified example of a commissioning timeline:
- Months 1 to 2: Pre-design involvement and commissioning plan
- Months 3 to 5: Design development review
- Months 6 to 9: Early construction site coordination
- Months 10 to 13: Mid-construction validation and preliminary testing
- Months 14 to 16: Late construction functional testing preparation
- Months 17 to 18: Final TAB and commissioning
- Months 19 to 20: Post occupancy seasonal review
I can provide a downloadable graphic version if desired.
Procurement Checklist for Hiring a TAB Contractor
Before awarding your contract, confirm the following:
- AABC, NEBB, or ACG certification
- Experience with new construction commissioning
- Sample TAB reports and commissioning documents
- Clear scope of work with milestone dates
- Insurance, safety, and compliance credentials
- Team availability for schedule critical periods
- Experience with Florida-specific cooling and humidity requirements
8. The Cost Impact of Late Stage Commissioning Involvement
When commissioning is brought in after major mechanical installation is complete, the project team often faces significant rework. Mechanical systems may need to be reopened, control wiring corrected, or ductwork modified to meet airflow requirements. In Florida’s competitive construction market, these changes frequently create delays that impact occupancy and revenue. Early involvement avoids these issues and keeps final commissioning aligned with the project’s intended schedule.
9. Coordination With Mechanical and Controls Contractors
Commissioning is most effective when TAB partners coordinate closely with mechanical and controls teams. During new construction, this collaboration ensures that dampers, valves, sensors, and VAV boxes are installed correctly and accessible for testing. It also helps validate the sequence of operation programming long before system startup. Strong coordination reduces troubleshooting time, eliminates guesswork, and improves overall building performance.
10. Documentation and Reporting Requirements for New Construction Commissioning
Successful commissioning depends on accurate documentation. TAB teams produce detailed reports that verify airflow, equipment functionality, and compliance with design intent. During new construction, these documents are required for final inspections, occupancy approvals, and warranty validation. Standard deliverables include equipment startup sheets, point-to-point BAS checks, airflow summaries, and final TAB reports. Proper documentation provides long-term value for facility managers who rely on accurate performance data.
11. Common Scheduling Delays and How to Avoid Them
Several avoidable setbacks can disrupt the commissioning schedule. These include incomplete equipment startups, missing control points, uncalibrated VAV boxes, and mechanical spaces not ready for testing. Delays also occur when commissioning is scheduled too close to the project’s closeout phase. Including TAB milestones in the construction timeline and confirming readiness with each trade helps prevent these issues. Early coordination is the most effective strategy for maintaining schedule continuity.
12. Integrating TAB With Sustainability and Energy Efficiency Goals
Many new construction projects in Florida pursue energy-efficient design strategies or certifications that require documented performance validation. Commissioning supports these goals by verifying ventilation rates, confirming system optimization, and identifying opportunities for long-term energy savings. TAB involvement ensures that HVAC systems meet design performance criteria and operate within expected efficiency ranges. This improves comfort, reduces energy costs, and supports sustainability objectives for the entire facility.
Conclusion
Hiring your TAB contractor early is one of the most effective ways to protect your schedule, reduce rework, and ensure your building delivers the performance you expect. When commissioning and TAB begin in the pre-design and design development stages, you gain better coordination, improved documentation, lower risk, and a smoother path to occupancy.
With more than 50 years of combined experience and over 15,000 successful Florida projects, Southern Independent Testing Agency provides reliable commissioning services that help your building operate as intended from day one.
If you are planning a new construction project and want a commissioning timeline that stays on track, SITA can support you at every phase.
