A Title 24 report does not always pass on the first calculation, and even a passing CF1R may need to be revised later if the construction drawings or equipment selections change. In most residential projects, the problem is not that the entire design is inefficient. More often, a few details—such as window performance, insulation, HVAC specifications, or inconsistencies between the plans and the energy model—need to be corrected.
What Does It Mean When a Title 24 Report “Fails”?
For projects using the performance method, approved compliance software compares the proposed building against the Energy Code baseline. If the proposed design does not meet the required energy budget, changes are needed before the Certificate of Compliance can be finalized. The 2025 Energy Code allows performance modeling specifically so different building components can be evaluated together rather than requiring every component to follow a single prescriptive solution.
A report can also pass the energy calculation but still require revision if the information in the CF1R does not match the permit drawings.
| SITUATION | WHAT HAPPENS | TYPICAL CAUSE | USUAL SOLUTION |
|---|---|---|---|
| ENERGY MODEL DOES NOT COMPLY | Calculation shows insufficient compliance margin | Envelope or equipment performance | Improve selected measures |
| CF1R AND PLANS DISAGREE | Plan reviewer requests correction | Design changed after modeling | Update report or drawings |
| REQUIRED INFORMATION IS MISSING | Report cannot be finalized accurately | Incomplete plans | Obtaining missing information |
| WRONG COMPLIANCE PATH IS USED | Forms may need to be replaced | Incorrect project classification | Reevaluate scope and form type |
Window Information Is a Common Problem
Windows can significantly influence residential energy performance. Their size, orientation, U-factor, and Solar Heat Gain Coefficient (SHGC) are all considered by the Energy Code.
Problems often occur when the architectural window schedule changes after the energy model has already been prepared.
| WINDOW ISSUE | WHY IT MATTERS | EXAMPLE | POSSIBLE CORRECTION |
|---|---|---|---|
| HIGHER U-FACTOR | More heat transfers through the window | 0.30 specified instead of 0.24 | Select better-performing glazing |
| HIGHER SHGC | More solar heat enters the home | Large west-facing windows | Lower SHGC |
| WINDOW AREA INCREASES | More glazing changes envelope performance | Larger sliding door added | Update the energy model |
| ORIENTATION CHANGES | Solar exposure changes | Window moves from north to west | Recalculate the project |
Insulation and Building-Envelope Details
Missing or inconsistent insulation information is another frequent reason a report needs correction. Wall construction, ceiling or roof insulation, raised floors, and other envelope assemblies should match between the architectural drawings and the CF1R.
| COMMON ISSUE | WHAT THE REPORT NEEDS | TYPICAL PLAN PROBLEM | POSSIBLE FIX |
|---|---|---|---|
| WALL INSULATION UNCLEAR | Insulation value and assembly | Plans only say “insulated wall” | Add specific R-value |
| ROOF ASSEMBLY CHANGES | Accurate roof/ceiling construction | Attic changed to vaulted ceiling | Update energy model |
| FLOOR TYPE INCORRECT | Correct thermal boundary | Raised floor modeled as slab | Correct construction type |
| INSULATION REDUCED | Actual installed value | R-value changed during design | Recalculate or restore specification |
The California Energy Commission’s residential compliance manual provides separate requirements for building-envelope components including fenestration, insulation, roofs, and floors.
HVAC and Duct Changes
HVAC changes can affect both the energy calculation and the field-verification requirements shown on the CF1R.
For example, replacing equipment, modifying ducts, changing system efficiency, or switching between ducted and ductless systems may change the required compliance documentation. Under the 2025 Energy Code, certain alterations also trigger duct-leakage testing and ECC verification requirements.
| HVAC CHANGE | POSSIBLE EFFECT | EXAMPLE | RECOMMENDED ACTION |
|---|---|---|---|
| EQUIPMENT EFFICIENCY CHANGES | Energy performance changes | Different heat-pump model selected | Update equipment data |
| DUCT LOCATION CHANGES | Distribution losses may change | Ducts moved into attic | Recheck calculations |
| EXISTING DUCTS ARE ALTERED | Testing may be triggered | HVAC system replacement | Confirm ECC requirements |
| SYSTEM TYPE CHANGES | Compliance strategy may change | Ducted system becomes mini-split | Revise mechanical inputs |
The Plans and CF1R Must Stay Consistent
One of the easiest problems to avoid is a mismatch between the energy report and the final drawings.
If an architect changes a window, insulation value, HVAC system, water heater, or conditioned floor area after the Title 24 report is prepared, the energy consultant should review the change before permit submission.
The CF1R is intended to demonstrate that the project design and equipment are compliant at the time of permit application.
How Can Revisions Be Minimized?
The best approach is simple: provide a coordinated plan set and avoid finalizing the CF1R while important design decisions are still changing.
A draft review is also valuable. Checking the project address, floor area, windows, insulation, HVAC system, and water heater before registration can catch many problems early.
Need Help With a Title 24 Revision?
If your project has received plan-check comments or the design has changed after the original CF1R was prepared, send us the latest drawings and the existing report. We can review the changes and determine what needs to be updated.
For new projects, no upfront payment is required. You can review the draft CF1R report before payment.
