What We Need to Prepare Your ADU Title 24 Report
An ADU Title 24 report is built from your plans, so the quality of the plan set decides how quickly the energy model can be finished.
For most ADUs, the plan set should include:
- Floor plan with dimensions, room names and ceiling heights
- Exterior elevations showing every window and exterior door
- Building sections or construction notes describing the wall, roof/ceiling and floor assemblies
- Window and door schedule with sizes, and the product ratings if windows have already been selected
- Site plan with the project address and a north arrow, so the model can orient each wall and window correctly
- Heating, cooling and water heating — the system type (for example a ducted heat pump, a ductless mini-split or a heat pump water heater) and where any ducts will run
- For conversions and attached units, a note of which walls, floors and ceilings are existing to remain and which are new
If something is not decided yet, tell us in the project notes and we will model a code-compliant assumption you can build to. Our guide to what documents to upload covers each item in more detail.
How the Energy Model Changes by ADU Type
The type of ADU changes which surfaces are modeled and what counts as existing construction. Whether a particular unit needs a report at all is covered in our guide to ADU energy compliance; this section explains what changes inside the report.
Detached ADU
A detached ADU is modeled as a complete new building. Every exterior wall, the roof and the floor (slab or raised) are entered, along with each window's size and orientation. Solar PV applicability is checked as part of the report.
Attached ADU
An attached ADU shares at least one wall, floor or ceiling with the main house. The model focuses on the ADU's own exterior envelope and systems, and the shared assemblies are entered as separations between conditioned spaces rather than as exterior walls. It also matters whether the ADU has its own heating and cooling or connects to the main house's equipment. Depending on the scope, an attached ADU may be modeled as new construction or as an addition to the existing home.
Garage Conversion ADU
A garage conversion turns unconditioned space into living space, so the existing slab, walls and roof become part of the conditioned envelope. The report records which assemblies are existing and which are being upgraded, how the old garage door opening is filled in, and the new heating and cooling system. We cover this project type in depth on our garage conversion Title 24 service page.
JADU Title 24
A JADU is created within the walls of an existing single-family home. Its energy scope depends on the space being converted. If the JADU uses rooms that are already heated and cooled, the energy work is usually limited to what actually changes, such as new windows, new equipment or altered ducts. If it converts previously unconditioned space, such as an attached garage, that area is modeled much like an addition.
How Your Climate Zone Affects an ADU Report
California is divided into 16 energy climate zones, and your project address sets the zone used in the report. The zone changes the energy budget the ADU is measured against and several prescriptive requirements. In hot inland zones the model is most sensitive to cooling loads, window solar heat gain and roof construction. In cooler coastal and mountain zones, heating loads and insulation carry more weight.
The same ADU plan can comply easily on one lot and need upgrades on another. Most ADUs use the performance method, where the design is modeled in CEC-approved software and compared with a code-defined standard design for the same building in the same zone. Title 24 calculations explains how that comparison works.
ADU Report Pricing, Turnaround and Delivery
| Item | Detail |
|---|---|
| Base price | $199, includes ADUs up to 1,000 sq ft |
| Larger ADUs | +$9 per additional 100 sq ft |
| Standard turnaround | 2–3 business days after we receive complete plans |
| 24-hour rush | +$49 |
| Super Rush (same day) | +$150, typically within a few hours; contact us for urgent projects |
| Revisions | Two revisions included |
The final price follows the square footage shown on your plans. If an adjustment is needed, we contact you before any work starts. For what else affects the price, see Title 24 report cost, and for deadlines see rush and same-day service.
What you receive
- A permit-ready PDF of your CF1R (Certificate of Compliance), delivered by email
- Registration with the CHEERS data registry where your project requires it
- Any HERS field verification items the design depends on, so you can schedule testing ahead of final inspection
More ADU Title 24 Questions
Does a small ADU, such as a 500 sq ft ADU, still need Title 24?
Generally, yes. Size alone does not usually exempt a new ADU from energy compliance, and small units are modeled the same way as larger ones. Some requirements, such as solar PV, have exceptions that depend on the project and the code cycle, and the report determines which ones apply.
Can I reuse a Title 24 report for the same ADU plan on another lot?
Usually not. The address, climate zone and orientation are all inputs to the energy model, so a plan that complies on one lot can give a different result on another. Each site normally needs its own report.
What if I change windows or HVAC equipment after the report is done?
Changes to energy features can change the result, so the report should match what is built. Two revisions are included. See what happens if your plans change.
Will the report tell me which items need HERS testing?
Yes. The CF1R lists any field verification items, such as duct leakage or ventilation testing, that a HERS rater must check after installation. See how HERS verification works.
