Title 24 Room Addition Reports — CF1R Energy Compliance for Home Additions
Title 24 Calcs prepares Title 24 CF1R energy compliance reports for room additions throughout California. We cover single-story additions, second story additions, and master suite additions. We also handle family room additions and sunroom additions. Most addition reports are ready within 1 to 2 business days starting at $250. See our cities service area for your location. Read our 2025 Title 24 code changes guide for the full update summary.
Who Needs a Title 24 Room Addition Report?
Specifically, California requires a Title 24 energy compliance report for every room addition that adds conditioned floor area. Specifically, this applies to all permits submitted on or after January 1, 2026. Specifically, the 2025 code sets minimums for new walls, ceilings, floors, windows, and HVAC systems in the addition scope. Furthermore, the compliance path — alteration versus new construction — determines which requirements apply to your specific project.
Title 24 Calcs prepares room addition reports for homeowners, contractors, architects, and designers throughout California. Additionally, we register every CF1R with an approved HERS provider before delivery. This means your report arrives ready for building department submittal without any further steps.
Title 24 Room Addition Report — key facts:
• Code: 2025 California Building Energy Efficiency Standards — effective January 1, 2026
• Addition types: Single-story, second story, master suite, family room, sunroom, patio enclosure
• Climate zones: All 16 California climate zones covered
• Starting price: $250 | Turnaround: 1 to 2 business days
• Includes: CF1R report, HERS registration, plan-sized PDFs, revision support
What Triggers a Title 24 Report for a Room Addition
Specifically, any room addition that adds conditioned floor area triggers a Title 24 energy compliance report. Specifically, conditioned floor area means any space that includes heating or cooling. Furthermore, most additions include at least one energy system. This makes a Title 24 report necessary for nearly all permitted additions.
Addition Types That Trigger a Title 24 Report
These addition types commonly trigger a Title 24 report:
- Single-story room addition — any new room added to the existing footprint, including bedrooms, bathrooms, and living spaces
- Second story addition — adding a full or partial second floor to an existing single-story home
- Master suite addition — a bedroom and bathroom addition, typically at the rear of the home
- Family room or great room addition — expanding the main living area of the home
- Sunroom or patio enclosure addition — enclosing an existing patio or adding a sunroom with heating or cooling
- Garage conversion with addition — converting a garage and adding new square footage simultaneously
Not Sure if Your Addition Needs a Report?
Moreover, unconditioned additions without heating or cooling typically do not trigger a Title 24 report. However, if the scope later changes to include HVAC, a report becomes necessary. We recommend confirming with your building department before starting any addition.
Title 24 Requirements for Room Additions — 2025 Code
Under the 2025 code, all new elements within the addition scope must meet current minimum performance standards. Specifically, only the new work needs to meet current standards — not the entire existing home. This is the fundamental difference between the addition compliance path and the new construction path.
| Element | 2025 Requirement | Applies To |
|---|---|---|
| Wall insulation | R-15 minimum for 2×4 walls | All new exterior walls in the addition |
| Ceiling insulation | R-38 minimum | All new ceilings and roof assemblies |
| Floor insulation | R-19 minimum where applicable | Floors over unconditioned spaces |
| Windows | U-factor ≤ 0.30, SHGC ≤ 0.23 | All new windows in the addition |
| HVAC equipment | 2025 minimum efficiency ratings | New equipment added in the scope |
| Duct leakage | Maximum 5% of system airflow | New ductwork added in the scope |
| Lighting | JA8 high-efficacy fixtures required | All new lighting fixtures in the addition |
Climate zone matters significantly for room addition insulation requirements. Zone 15 additions require more insulation than Zone 7 additions. This affects project cost and HVAC sizing. Window SHGC requirements also vary by zone. Hot climate zones have stricter solar heat gain limits to reduce cooling loads.
How Title 24 Calcs Handles Addition Reports
We specify the correct insulation values, window minimums, and HVAC requirements for your climate zone on every addition report. Additionally, we flag any potential HERS verification requirements so your contractor can prepare before construction begins.
Addition Compliance Path — Alteration vs New Construction
Room additions in California typically follow the alteration compliance path. Under this path, only the new work must meet current 2025 standards. The existing home does not need upgrading unless the scope specifically includes existing systems. Consequently, this approach makes room addition compliance significantly less complex than new construction compliance.
However, some building departments classify large additions as new construction. This happens when the addition exceeds a certain percentage of the existing home’s floor area. In those cases, full new construction requirements apply. These include solar PV, battery readiness, and heat pump baselines for the entire structure. Title 24 Calcs confirms your building department’s classification before starting any report.
| Factor | Alteration Path | New Construction Path |
|---|---|---|
| Scope covered | New work only | Entire structure |
| Solar PV | Usually not required | Mandatory |
| Battery readiness | Usually not required | Mandatory |
| Heat pump baseline | Applies to new HVAC only | Applies to entire home |
| Complexity | Lower — faster to prepare | Higher — full modeling required |
Most room additions follow the alteration path. The performance path works well when installing a new heat pump is not practical. See our prescriptive vs performance guide for a full comparison. Consequently, solar PV and battery readiness typically do not apply. Therefore, this keeps addition compliance simpler and less costly than new construction compliance. We confirm your path with your building department before starting your report.
CF1R, CF2R, and CF3R for Room Additions
Specifically, room additions follow the same three-certificate compliance system as all California residential construction. Specifically, the CF1R accompanies the permit application. The CF2R confirms installation. The CF3R confirms field verification. Furthermore, all three must register with an approved HERS provider before the building department issues a certificate of occupancy.
| CF1R Certificate of Compliance. Title 24 Calcs prepares this. Submitted with the permit application. Shows the addition design meets current energy code requirements. | CF2R Certificate of Installation. The installing contractor signs this after installing each energy system — insulation, windows, HVAC, and lighting fixtures. | CF3R Certificate of Verification. A certified HERS Rater signs this after verifying duct leakage and heat pump refrigerant charge where applicable. |
HERS Testing for Room Additions
HERS testing applies to room additions when the scope includes new HVAC equipment or new ductwork. Furthermore, a certified HERS Rater visits after installation and verifies that systems perform as your CF1R specifies. Moreover, your building department requires this verification before issuing a certificate of occupancy.
HERS Measures That Apply to Room Additions
These HERS measures commonly apply to room additions:
- Duct leakage testing — applies when new ductwork goes into the addition. Specifically, duct systems must leak less than 5 percent of system airflow. This is the most commonly required HERS measure on addition projects.
- Heat pump refrigerant charge verification — applies whenever a new heat pump replaces or supplements the existing HVAC system. Under the 2025 code, this measure covers all 16 California climate zones.
- Whole-house ventilation flow rate — applies when the addition scope includes new mechanical ventilation. The HERS Rater confirms the system delivers the required fresh air volume.
Notably, not all room additions require HERS testing. An addition without new HVAC equipment or new ductwork typically has no HERS measures. In that case, the contractor completes the CF2R for insulation, windows, and lighting. No HERS Rater visit applies.
Therefore, your CF1R clearly identifies which HERS measures apply to your specific addition scope. The California Energy Commission maintains the official list of approved HERS providers throughout California.
Room Addition Requirements by Climate Zone
Moreover, room addition energy requirements vary across California’s 16 climate zones. Specifically, insulation values, window performance minimums, and HVAC efficiency thresholds all differ by zone. Therefore, Title 24 Calcs confirms your exact climate zone by parcel address before starting any report.
We serve room addition projects across all California climate zones. Key cities we cover include Irvine, Anaheim, Corona, Temecula, and Murrieta. We also cover Fontana, Rancho Cucamonga, Ontario, and San Bernardino. Furthermore, we serve Sacramento, Fresno, Chula Vista, Carlsbad, Palm Springs, and Palm Desert. See our full California climate zones guide and cities service area for all locations.
Frequently Asked Questions — Title 24 Room Additions
Does a room addition in California need a Title 24 report?
Yes. Any room addition that adds conditioned floor area requires a Title 24 energy compliance report. Specifically, this applies to all permits submitted on or after January 1, 2026. Furthermore, a report prepared under the 2022 code will not pass plan check after that date.
Does my room addition need solar PV?
Most room additions follow the alteration compliance path. Consequently, solar PV typically does not apply. However, some building departments classify large additions as new construction. In those cases, solar PV requirements may apply. Furthermore, Title 24 Calcs confirms your classification before starting your report.
Does HVAC replacement in a room addition need HERS testing?
Yes. Any new HVAC equipment or new ductwork in an addition scope triggers HERS verification. A certified HERS Rater must verify duct leakage and heat pump refrigerant charge. This must happen before the building department issues a certificate of occupancy.
Do existing walls in my home need upgrading for a room addition?
Under the alteration compliance path, only the new work must meet current standards. Only the new work within the permitted scope must reach current standards. Consequently, the rest of the home stays as-is.
How much does a Title 24 room addition report cost?
Pricing starts at $250 for eligible room addition projects. This includes the CF1R, HERS registration, plan-sized PDFs, and revision support. See our pricing page for current rates.
How long does a Title 24 room addition report take?
Most room addition reports are ready within 1 to 2 business days after we receive complete plans. Furthermore, rush options are available for urgent submittals.
What plans do I need to provide?
Provide a floor plan with dimensions and north arrow, exterior elevations, window schedule, equipment type, and project address. In practice, more complete plans mean faster delivery.