Simpson Strong Tie

HVAC Reliability and Value Engineering 

Client: Simpson Strong-Tie
Location: Gallatin, TN
Facility: New manufacturing campus (two buildings)
Scope: Commercial rooftop HVAC system supporting manufacturing and office areas
Units: 41 rooftop units (Daikin Maverick) + associated distribution (VAV boxes installed by others)
Installing Contractors: Cornerstone Mechanical (RTUs + VAV), ICON (process scope + chiller/pumps, ongoing maintenance)
Owner’s Rep: Dillard Adams

Dangle
SST2

The Challenge

Simpson Strong-Tie planned a major expansion to bring distributed processes in-house and reduce shipping costs. The initial basis of design defaulted to equipment the owner had previously experienced issues with—specifically service delays tied to proprietary parts and limited servicing options. Extended downtime had created operational disruption and forced production shifts to protect employee comfort and safety.

Additionally, the project faced:

  • Tight schedule and staging constraints (limited on-site laydown area)
  • Structural and safety considerations related to setting heavy rooftop equipment
  • Refrigerant transition timing risk impacting equipment availability and owner preferences

Mechanical Engineering Solutions

MRG Identified a $300,000 opportunity of savings, including: 

  • Return duct strategy optimization
    • Reduced extensive return ductwork by implementing corridor returns where appropriate
    • Approximately $200,000 in ductwork
  • Exhaust/purge strategy refinement
    • Leveraged economizer fresh air capability and variable exhaust options integrated with rooftop units
    • Reduced need for separate louvers and dedicated exhaust fans while improving purse capacity
    • Approximately $100,000 in savings

 

Heli

Logistics and Schedule Risk Mitigation

To address equipment timing and refrigerant transition concerns: 

  • Organized early release of equipment. 
  • Coordinated secure offsite storage at a protected crane yard (Century Steel)
  • Supported phased delivery and staging aligned with crane/helicopter lifts

The solution

MRG collaborated with the owner team and engineer to evaluate alternatives and recommended Daikin Maverick commercial rooftop units, selected for:

  • Dual refrigeration circuits to maintain operation if one circuit fails
  • Redundant heating (two burners) for improved heating uptime
  • Serviceability features (hinged panels, accessible components)
  • Non-proprietary components to reduce “single-source parts” downtime risk

MRG also conducted a critical review of the mechanical design and proposed value-engineering changes that reduced the scope without sacrificing performance.

Units
last 2

The result

  • Improved reliability strategy through redundancy and serviceable equipment selection
  • Reduced downtime risk through non-proprietary parts flexibility
  • Delivered meaningful mechanical engineering savings
  • Supported installation readiness and schedule protection despite significant coordination constraints