Permitting basics · Required Documents & Filing
Florida energy calcs: which form your permit needs, and what gets it kicked back
By David Gizys · Founder & President
Updated September 22, 2026 · 8 min read
Plan review sent the package back over the energy calc
It is usually the shortest document in a residential submittal and one of the most reliable ways to lose a week. The drawings are sealed, the site plan is clean, and the comment that comes back is that the energy form does not match the plans — a window SHGC that changed after pricing, a ceiling R-value that never made it into the wall section, an air handler that moved into the garage after the model was run.
What everyone on a jobsite calls the energy calc is really two things: a compliance path chosen out of the Florida Building Code, Energy Conservation, and the signed form that documents it. That distinction matters because a mismatch is rarely a typo. Fixing it means re-running the model and revising sealed drawings to agree with it, which is why this one page of the permit document package punches so far above its size.
Energy is also one of the few disciplines a reviewer can check against your drawings without leaving the desk. The numbers on the form either appear in the plans or they do not, so it is a cheap comment to write and an expensive one to answer. Here is what the form is actually claiming, and what has to ship alongside it before plan review will move the job forward.
The three residential compliance paths
One- and two-family homes and townhouses three stories or less have three ways to demonstrate compliance. They are not interchangeable, and the choice constrains your glazing, insulation and equipment.
- R402 — prescriptive (Form R402) — The building meets or exceeds every efficiency requirement and applicable mandatory requirement summarized on the form. Simplest to document, least room to trade one assembly against another.
- R405 — simulated performance (Form R405) — The house is modeled in approved software against a baseline. Under the 8th Edition the model has to land at an e-ratio of 0.95 or better to pass, so a design that cleared the prior edition does not automatically clear this one.
- R406 — energy rating index (Form R406) — The Energy Rating Index alternative. Like R405, it is the path you reach for when a design will not comply prescriptively — an aggressive glass package being the usual reason.
- The choice is a design decision, not paperwork — Prescriptive is cheapest to produce and the most restrictive to build to. Performance buys design freedom and buys it by committing you to numbers somebody has to verify in the field later.
Run the calc before the drawings are finished, not after
The most common sequencing mistake is treating the energy calc as something you order once the set is done. Window performance, insulation values, duct location and equipment selection are inputs to the model. Order the calc last and you have built a set around assumptions the model may not support.
Run the other direction. Settle the compliance path while the envelope is still being drawn, hand the modeler the real assemblies, and let the form's numbers land in the drawings rather than contradict them. We assemble and file the whole package this way, which is a large part of how intake to submission typically runs about a week instead of a month — most of what people experience as permitting delay is document sequencing, not government speed.
Worth knowing which county you are in before the first submittal, too. The code is statewide but the checklist in front of the reviewer is not, and departments differ on what they want attached and in what order. On the Gulf coast — Sarasota County and its neighbors — you are working in Climate Zone 2, which sets the prescriptive table your project gets measured against.
What ships alongside the form
The signed compliance form is the cover sheet. Under the performance paths, these are the attachments reviewers expect with it.
- The Air Barrier and Insulation Inspection Component Criteria checklist — Required documentation when you comply under R405 or R406. It is the item most often missing from an otherwise complete package.
- A completed Envelope Leakage Test Report — The form claims an air leakage rate. This is the report that carries it.
- A completed Duct Leakage Test Report — Required if the duct leakage type on the form is anything other than default leakage. Claim a tested number and you have committed to producing the test.
- HVAC equipment documentation — Manufacturer and model number of the outdoor and indoor units, submitted with the sensible and total cooling capacities at the design conditions the code specifies.
A reviewer comparing the energy form to the drawings is checking the same values twice. If the window schedule, the wall and ceiling assemblies, or the air handler location on the plans disagree with what was modeled, the comment writes itself — and the fix usually lands back on the design professional, not on the form.
An energy calc is not a Manual J
These get used as synonyms constantly and they are two different documents answering two different questions. The energy form proves the envelope and systems meet the energy code. A load calculation proves the equipment is sized to the house that was actually drawn.
Section R403.7 is the mandatory one for sizing: heating and cooling equipment is selected per ACCA Manual S based on loads calculated per ACCA Manual J or another approved methodology. The code does not allow designer safety factors or provisions for future expansion, which is the part that surprises people — the habit of rounding a system up a half ton is not a code-compliant practice, it is an open comment waiting to happen.
So a set can pass the energy form and still draw a comment on equipment sizing. If your mechanical sub picks the unit off the last house they did, expect that conversation.
The numbers somebody has to hit in the field later
Everything claimed on the form eventually gets tested, and the testing happens when the house is nearly finished and the schedule has no slack left. Two thresholds are worth knowing before you commit to them on paper.
Air leakage, under Section R402.4.1.2, is tested and verified at a rate not exceeding seven air changes per hour in Climate Zones 1 and 2 — all of the coastal work this office handles. Testing follows ANSI/RESNET/ICC 380 and is reported at a pressure of 0.2 inch w.g., which is the 50 pascals the blower door crew will quote you. There is a floor as well as a ceiling: a dwelling unit that tests tighter than three air changes per hour has to be provided with whole-house mechanical ventilation. Build tighter than you planned for and you have added a piece of equipment.
Duct leakage runs on its own numbers. Total leakage is 4 cfm per 100 square feet where an air handler is installed at the time of the test and 3 cfm per 100 square feet where it is not. The total leakage test is not required for ducts and air handlers located entirely within the building thermal envelope, which is a genuine argument for conditioned mechanical space rather than an attic run.
Who performs the test is also regulated — testing is done by individuals defined in s. 553.993, Florida Statutes, or by contractors licensed under the relevant categories of s. 489.105(3). Line that up early, the same way you would line up private provider inspections, rather than discovering at certificate of occupancy that nobody booked it.
Which edition of the code will review your job
This is live right now. The 9th Edition (2026) Florida Building Code, Energy Conservation carries an effective date of December 31, 2026, and it updates the 8th Edition against the 2024 International Energy Conservation Code rather than the 2021 edition underneath the current code. The Florida Building Commission publishes the analysis of changes for the residential energy code at floridabuilding.org.
Generally the date the application is submitted and accepted governs which edition reviews the job for the life of that permit. If you have designs sitting on the shelf waiting on financing or a survey, that timing is worth a conversation with your building department now rather than a redesign later — and confirm the changeover date with them, because code adoption schedules move.
Commercial runs off a different chapter entirely
If the project is not a one- or two-family home or a townhouse three stories or less, none of the R-forms above apply. Commercial compliance lives in Chapter 4 [CE] of the same code, with ASHRAE 90.1 available as an alternate compliance path and ComCheck as the usual tool for documenting it. Lighting controls under Section C405 are the reliable source of comments there, the way glazing is on the residential side.
Either way the failure mode is the same and it is not really about energy. It is about a document that disagrees with the drawings it was supposed to describe. Catching that before the plans are sealed is most of what getting a package permit-ready actually consists of.
Have a set that needs an energy path settled before it gets sealed?
Tell us about your project. We reply within one business day — and we’ll tell you straight whether we’re the right fit.
Frequently asked questions
- What is an energy calc in Florida?
- It is the signed form demonstrating that a building complies with the Florida Building Code, Energy Conservation, plus the documentation that backs the claims on it. For residential work that means Form R402, R405 or R406, depending on which compliance path the design uses, along with attachments such as the Air Barrier and Insulation Inspection Component Criteria checklist and the envelope and duct leakage test reports. It is part of the standard permit document package for a new home.
- Which energy form does my project need — R402, R405 or R406?
- R402 is the prescriptive path: the building meets or exceeds every efficiency and applicable mandatory requirement summarized on the form. If the design will not comply that way — usually because of the glass package — it can still comply under Section R405, the simulated performance path, or Section R406, the Energy Rating Index alternative. The practical rule is that prescriptive is cheapest to document and most restrictive to build to, and performance buys design freedom in exchange for numbers that have to be verified later.
- Is an energy calc the same thing as a Manual J?
- No. They are separate documents answering separate questions. The energy form proves the envelope and systems meet the energy code; a Manual J load calculation feeds equipment selection under Section R403.7, which requires sizing per ACCA Manual S based on loads calculated per ACCA Manual J or another approved methodology. That section also does not allow designer safety factors or provisions for future expansion, so a set can satisfy the energy form and still draw a comment on an oversized system.
- When is a blower door test required?
- Section R402.4.1.2 requires the building or dwelling unit to be tested and verified as having an air leakage rate not exceeding seven air changes per hour in Climate Zones 1 and 2, which covers Florida's coastal counties. Testing is conducted in accordance with ANSI/RESNET/ICC 380 and reported at 0.2 inch w.g., or 50 pascals. Note the other end as well: a dwelling unit testing tighter than three air changes per hour must be provided with whole-house mechanical ventilation.
- When does the 9th Edition energy code start applying to permits?
- The 9th Edition (2026) Florida Building Code, Energy Conservation carries an effective date of December 31, 2026, and updates the current code against the 2024 International Energy Conservation Code. Generally, the edition in effect when an application is submitted and accepted governs that permit for its life, so the submittal date matters more than the construction date. Because adoption schedules can shift, confirm the changeover with the building department reviewing the job before you plan a design around it.
“Permit-ready in a week instead of a month. David caught two tabulation errors before submission that would have bounced us. Worth every dollar.”— Custom Home Builder, Anna Maria Island
This is part of our Required Documents & Filing service. Tell us about your project and we’ll handle it end to end.