Load Calculations for Florida Commercial HVAC Replacement Permits
Florida-licensed PE
When a commercial change-out changes the system's capacity, Florida building departments can ask for a load calculation with the permit application. We prepare it, stamped by a Florida-licensed professional engineer.
Replacing a commercial air conditioning system in Florida usually starts as a like-for-like swap. When the new equipment has a different capacity from the old, the building department may ask for a load calculation. We prepare stamped cooling and heating load calculations for commercial change-outs anywhere in Florida.
When a change-out needs a load calculation
Each building department sets its own permit checklist, so the rule varies by county and city. Charlotte County's HVAC Replacement Application for Commercial Buildings (Florida Building Code, 8th Edition) is one example:
- When both the air handler and the condenser are replaced and the capacity changes, heating and cooling load calculations go in with the permit application.
- When the new unit's tonnage is more or less than the existing system's, the application asks for a detailed explanation of the difference.
- Commercial alterations with ductwork changes go to plans review.
A load calculation answers the question behind the first two: how much cooling and heating the space needs. Check the checklist of the department you are permitting with to see what it requires.
What you get
- Room-by-room cooling and heating loads by ASHRAE methods, worked from the building as it is now, from the information you send
- Ventilation rates to the Florida Building Code, Mechanical
- The latent load worked explicitly, which matters in Florida's humid climate
- A stamped document, sealed by a Florida-licensed professional engineer
The load calculation gives the capacity the replacement equipment must meet. The equipment itself is selected by the contractor.
Why the existing tonnage is not the answer
The equipment being replaced was sized for the building, the use and the code of its day. Since then the tenant may have changed, walls may have moved, windows and lighting may have been replaced, and the ventilation the code requires may be different. A load calculation worked from the building as it is now gives the capacity the space needs today, which the contractor can compare with the old tonnage.
What to send
- A floor plan with dimensions, or the original drawings if they exist
- Window sizes and types, and the roof and wall construction where known
- How each space is used and how many people it holds
- The existing equipment's nominal tonnage and which areas each unit serves
- The turnaround you need
If something is missing, we send a list of what is still needed; see an example of a clear response.
Turnaround and fee
Enter the project type and square footage in the online quote tool and, for most projects, a preliminary fee appears on screen. The fee is confirmed in writing once we review the scope. Inquiries are answered within 1 to 2 business days, and most load calculations are returned within 5 to 10 business days of scope confirmation. Rush turnarounds are available when the schedule requires one.