Title 24 California Compliance: A 2026 Checklist for New Construction

Most Title 24 problems on new construction are sequencing problems. The code itself is knowable, the forms are published, the software is free, and the requirements are not secret. What goes wrong is order. A facade is detailed before anyone has decided which compliance path the project is on. A plant room is sized before the mechanical baseline is confirmed. A roof is committed to mechanical equipment before the photovoltaic array is laid out. Each of those is a small decision at the time and an expensive one six months later.

This is the working checklist version of the code. If you want the underlying explanation of what the standard is and how it is structured, read what Title 24 actually is first. What follows here assumes you already know that and want the order of operations for a new building entering permit under the 2025 Energy Code. Budlong delivers MEP engineering services across California and runs this sequence on every new build we touch, from single tenant industrial to acute care. Our expertise overview sets out the range.

1. What Is a Title 24 Compliance Checklist?

A Title 24 compliance checklist is the ordered list of decisions, calculations, documents and field tests that a new building has to complete to satisfy Part 6 of the California Building Standards Code, from the first massing study to the certificate of occupancy. It is not the same thing as the compliance forms. The forms are the output. The checklist is the process that produces them without rework.

The reason it needs to be a sequence rather than a list is that Part 6 is a closed system. Envelope performance feeds the load calculation. The load calculation feeds equipment selection. Equipment selection feeds the electrical service size. The service size feeds the photovoltaic and battery layout. The lighting power allowance interacts with the performance model. Change any one of them late and the chain has to be recalculated, which means the documentation package has to be reissued, which means plan check restarts.

Part 6 is written and maintained by the California Energy Commission, adopted through the California Building Standards Commission, and enforced by the local building department that issues your permit. Three bodies, one document, and no single point of contact who will tell you what you got wrong until plan check does.

2. How the 2025 Code Changes the Sequence

The 2025 Energy Code took effect for permit applications submitted on or after 1 January 2026. It is not a light touch update, and several of its changes move work earlier in the programme than it used to sit.

The metric behind compliance has changed

Building Energy Efficiency Ratings are now calculated on Long Term System Cost rather than the Time Dependent Valuation metric used for two decades. Energy budgets are expressed as Efficiency LSC, covering space conditioning, water heating, ventilation and lighting, and Total LSC, which adds photovoltaics, battery storage and demand flexibility. Because the relative weighting of gas and electric savings has shifted, a design that cleared the 2022 baseline comfortably can sit close to the margin under the 2025 code with identical equipment.

The mechanical baseline moved

The 2022 code introduced heat pump baselines for single zone systems. The 2025 code extends prescriptive requirements to multi zone systems serving offices and schools of not more than 150,000 square feet or five habitable storeys, with an exception for schools in Climate Zones 6 and 7. For a mid rise office building that is the single largest cost item in the cycle, because it changes plant type, plant room area, electrical service size and roof loading at once.

Ventilation is recalculated

Minimum outdoor air now comes from Equation 120.1-F, which takes the larger of an occupant based rate and an area based rate. Tables 120.1-A, 120.1-B and 120.1-C were updated for minimum ventilation rates, minimum exhaust rates and air stream classification. On many projects the result is more outdoor air than the previous method produced, which lands on air handler size, ductwork and energy recovery before the model is even run.

Two exemptions disappeared

The laboratory exemption has been removed, so laboratory spaces are now inside the compliance envelope and the requirements for laboratory and factory exhaust systems were updated with it. Separately, the Tailored Method for calculating indoor lighting power allowances has been withdrawn, with some of its allowances folded into the Area Category Method. Projects that relied on the Tailored Method to justify high illuminance in specialist spaces have lost that route.

3. The Twelve Stages, Mapped to Project Phase

The table below is the checklist in outline. Each stage has a natural home in the design programme, and the cost of moving one to the right is not linear.

Two things fall out of this table. Stages 2, 3 and 4 carry disproportionate weight, and they all sit in the first third of the programme. And stages 11 and 12 are the only ones where a failure cannot be corrected on paper.

4. Which New Construction Projects Are Captured

Every newly conditioned building in California falls under the full scope of Part 6. The useful question is not whether the code applies but which of its optional obligations attach to your particular building.

Photovoltaic and battery storage

Section 140.10 requires photovoltaics on newly constructed buildings across a wide list of occupancy types including offices, schools, retail and grocery, restaurants, warehouses, hotels and motels, libraries, religious worship, sports and recreation, events and exhibits, and multifamily buildings above three storeys. Mixed occupancy buildings are captured where at least 80 percent of floor area serves those uses. Exemptions exist where the Solar Access Roof Area is below 3 percent of conditioned floor area, where the calculated requirement falls below 4 kWdc, and where there are fewer than 80 contiguous square feet of usable roof.

Building commissioning

Section 120.8 requires the full commissioning process for new nonresidential buildings with 10,000 square feet or more of conditioned space. That covers Owner’s Project Requirements, Basis of Design, design review, a commissioning plan issued before permit, functional performance testing, a systems manual, operator training and a final commissioning report. Below that threshold the design review and documentation obligations still apply.

The multi zone heat pump baseline

Offices and schools of not more than 150,000 square feet or five habitable storeys now have a prescriptive multi zone heat pump baseline, with schools in Climate Zones 6 and 7 excepted. Above those thresholds the prescriptive requirement does not attach in the same way, which is one of the few places where a larger building has an easier compliance route.

5. Stage by Stage: What Each Building System Must Deliver

This is the technical core of the checklist. Each system has mandatory measures that apply regardless of compliance path, and prescriptive requirements that apply only if you chose the prescriptive route at stage 2.

Stage 3: Envelope and glazing

Fix insulation levels, fenestration U factor and solar heat gain coefficient, air leakage limits, and cool roof requirements. In the performance path this is also where the interaction between glazing area and orientation is tested. The envelope is committed earlier than any other regulated system and is the most expensive to revisit, which is why the path decision at stage 2 has to precede facade detailing rather than follow it. If the window to wall ratio is heading above roughly forty percent, assume the performance path and budget accordingly.

Stage 4: Mechanical baseline and loads

Equipment efficiency minimums, economizer requirements, fan power limits, duct sealing and insulation, zoning, demand control ventilation and the outdoor air calculation from Equation 120.1-F. Under the 2025 code, multi zone systems in qualifying offices and schools baseline to heat pump equipment, which in practice means variable refrigerant flow with dedicated outdoor air, four pipe fan coils served by air to water heat pumps, or variable air volume with equivalent plant.

Test that against the budget during HVAC system selection rather than discovering it at plan check. Accurate HVAC load calculations carry more weight than they used to, because heat pump plant is less tolerant of oversizing than the gas fired equipment it replaces, and the penalty for a generous safety factor now shows up in both capital cost and the compliance margin. Detailed HVAC design should not start until this baseline is agreed.

Stage 5: Service water heating

Efficiency minimums, pipe insulation, recirculation controls and heat pump water heating baselines. Central domestic hot water plant in hotels, multifamily and healthcare is where the electrification direction of the code is most visible, and where the plant footprint changes most. Heat pump water heating needs more space, more clearance, a source of air and a plan for the noise. Bring your plumbing engineering team into the space planning conversation, not just the riser diagram.

Stage 6: Lighting and controls

Indoor and outdoor lighting power allowances, mandatory controls, daylighting controls and receptacle controls. Under the 2025 code the daylighting trigger drops to 75 watts of general lighting in sidelit and skylit daylit zones, 60 watts for garages, and luminaires longer than eight feet must be controlled in segments of eight feet or less. The Tailored Method is gone. Projects with an architectural lighting design concept that depended on tailored allowances now have to carry that load in the performance model instead.

Stage 7: Photovoltaics and battery storage

Equation 140.10-A sets the minimum array by multiplying conditioned floor area by a capacity factor from Table 140.10-A. That result is capped by the Solar Access Roof Area available, at 14 watts per square foot for low sloped roofs and 18 watts per square foot for steep sloped roofs. Roof areas with less than 70 percent annual solar access, occupied roof areas and space reserved for other code compliance are excluded. The 2025 cycle raised capacity factors for libraries in most climate zones and for hotels and motels, medical offices, restaurants, retail and grocery across all zones.

Battery storage follows from the array. Equation 140.10-B sets usable energy capacity, 140.10-C adjusts where the array was sized from roof area, and 140.10-D fixes power capacity at usable energy divided by four. Exemptions apply where the installed array falls below 15 percent of the calculated requirement, where usable capacity is under 10 kWh, and for certain tenant spaces under 5,000 square feet. The practical consequence is that roof allocation and electrical room sizing are code driven decisions now, which makes early coordination between structural capacity, mechanical equipment layout and photovoltaic design unavoidable. The battery also has to be located, ventilated and served, which is an electrical engineering problem before it is a sustainability one.

6. CALGreen and the Adjacent Approvals

Part 6 is not the only thing in the permit set with sustainability content, and treating it as a standalone workstream is how late conflicts appear.

Stage 8a: CALGreen

Part 11 of Title 24, the California Green Building Standards Code, is mandatory statewide. It covers water efficiency, material conservation, construction waste diversion and indoor environmental quality, with voluntary Tier 1 and Tier 2 measures available where a jurisdiction has adopted them. Its indoor air quality provisions interact with the ventilation design set at stage 4, and its water efficiency provisions interact with fixture selection at stage 5. Run them together.

Stage 8b: Local reach codes

Dozens of California jurisdictions have adopted reach codes that go beyond the state baseline, most commonly on electrification, electric vehicle infrastructure and photovoltaic sizing. These are local ordinances, they change on local timetables, and they are the most frequently missed item on the entire checklist because the state code is what everyone researches. Confirm the reach code position with the jurisdiction at stage 1, not at stage 10.

Stage 8c: Voluntary certification

If the project is pursuing LEED, build one energy model that serves both the Part 6 submission and the energy performance credit rather than commissioning two. Because California’s code floor is unusually high, projects here often earn energy points more readily than equivalent buildings elsewhere. That coordination sits at the centre of how we scope LEED MEP services. The ASHRAE standards library is the reference point for most of the underlying methods, and the U.S. Department of Energy Building Energy Codes Program publishes the comparative analysis if you need to explain to a national owner why California is different.

7. Specialist Cases: Healthcare, Laboratories, Schools, Data Centres

Four building types run a modified version of the checklist, and in each case the modification affects stage 1 rather than stage 9.

Healthcare

Hospitals and skilled nursing facilities are reviewed by the Department of Health Care Access and Information rather than by the local building department, on a separate plan review track with its own timetable. Part 6 still applies, but it interacts with ventilation rates and pressure relationships that exist for infection control rather than energy reasons. Where the two conflict, patient safety governs and the energy analysis is built around the constraint. Our healthcare facilities teams run both tracks in parallel from concept.

Laboratories

The removal of the laboratory exemption is the most consequential 2025 change for life sciences developers. High exhaust volumes, once through air and process loads that previously sat outside the compliance envelope are now inside it, and the requirements for laboratory and factory exhaust systems were revised alongside. Any lab scheme carried over from a 2022 cycle project needs its ventilation strategy reassessed before the permit application. This affects our laboratory and industrial clients directly and usually pushes them onto the performance path.

Schools

K to 12 and community college projects are reviewed by the Division of the State Architect, which adds a review track with its own submittal requirements and timetable. Schools are also directly in scope for the new multi zone heat pump baseline, except in Climate Zones 6 and 7. Both facts belong in stage 1 for any education project.

Data centres and covered processes

Part 6 treats computer rooms as a covered process with dedicated efficiency and economizer requirements, documented on the PRC form family. As rack densities rise and liquid cooling moves into the mainstream, the distance between what the code contemplates and what modern facilities actually build has widened. These projects almost always need the performance path plus an early conversation with the authority having jurisdiction about how the covered process will be characterised.

8. Choosing the Compliance Path

This is stage 2, and it deserves its own section because it is the decision that determines how much of the rest of the checklist is negotiable. Make it at the end of schematic design, once massing and glazing ratios are settled but before the facade is detailed.

The failure pattern is consistent. A project starts prescriptive to save fee, hits a glazing, lighting or plant constraint during design development, then switches to performance halfway through. That switch costs more than starting on the performance path would have, because the model has to be built around a design that was never developed with modelling in mind. Under the 2025 code, with the Tailored Method withdrawn and laboratories brought into scope, the number of buildings that can comfortably stay prescriptive has fallen.

9. Documentation, Plan Check, Acceptance Testing and Occupancy

Stages 9 through 12 are where compliance becomes a permit condition rather than a design intent. None of them can be compressed by working harder, and two of them depend on people outside your team.

Stage 9: The documentation package

Four document families carry the record from design to occupancy, each split by subject area.

Subject areas run across ENV for envelope, MCH for mechanical, LTI for indoor lighting, LTO for outdoor lighting, LTS for sign lighting, PRC for covered processes, ELC for electrical, PLB for plumbing, SAB for solar and battery, and CXR for commissioning. Assign an owner to each family at stage 1. The NRCI forms in particular are frequently orphaned, because they belong to the contractor but nobody in the design team is watching for them.

Stage 10: Plan check

Submit the NRCC package with the permit set, not after it. Correction cycles are measured in weeks, and each cycle is a full round trip through the jurisdiction’s queue. The most common corrections we see are mismatches between the equipment schedule on the drawings and the equipment in the model, missing acceptance test forms in the submitted set, and lighting control narratives that do not match the controls actually specified. All three are avoidable with a coordination check before submittal.

Stage 11: Acceptance testing

Specified mechanical, lighting and control systems must be tested in the field to confirm they operate as the compliance documents claim. Testing must be performed by a technician certified through an Acceptance Test Technician Certification Provider approved by the Energy Commission. Certification is subject specific: lighting controls are covered by NLCAA and CALCTP, and mechanical systems by providers including the California State Pipe Trades Council, the National Energy Management Institute Committee and the Refrigeration Service Engineers Society.

Typical tests cover outdoor air economizer operation, demand control ventilation, supply fan variable flow control, valve leakage, hydronic controls, automatic daylighting controls, occupancy sensing and automatic shut off. Book the technicians when equipment submittals are approved. Certified technicians are a constrained resource in every California market and the certificate of occupancy depends on their availability.

Stage 12: Commissioning and occupancy

For new nonresidential buildings of 10,000 square feet or more, section 120.8 commissioning runs alongside acceptance testing and is a separate obligation with its own deliverables. Acceptance testing asks whether the installation matches the code submission. Commissioning asks whether it matches the owner’s requirements. Running them as separate exercises duplicates site visits and multiplies contractor disruption, which is why we scope commissioning services to absorb acceptance testing rather than sit beside it. The building commissioning process article sets out how the two dovetail in practice.

Key Takeaways

• Title 24 compliance is a twelve stage sequence, and the three stages that matter most all sit in the first third of the programme.
• The permit application date determines the code edition. The 2025 Energy Code applies from 1 January 2026.
• Choose the compliance path at the end of schematic design. Switching later costs more than starting on the performance path would have.
• Multi zone systems in offices and schools up to 150,000 square feet or five habitable storeys now baseline to heat pumps, except schools in Climate Zones 6 and 7.
• Minimum ventilation comes from Equation 120.1-F, taking the larger of an occupant based and an area based rate.
• Photovoltaics are sized by Equation 140.10-A and capped by Solar Access Roof Area at 14 or 18 watts per square foot. Battery storage follows from Equations 140.10-B, C and D.
• The laboratory exemption and the lighting Tailored Method are both gone, and the daylighting trigger has dropped to 75 watts with controlled segments of eight feet or less.
• Assign an owner to each of the NRCC, NRCI, NRCA and NRCV families at stage 1, and book ATTCP certified technicians at submittal approval.

10. Where Budlong Works

Title 24 is a statewide code, but the checklist runs differently in different jurisdictions. Plan check culture in Los Angeles is not the same as in San Francisco, reach codes add local requirements above the state baseline in dozens of cities, and utility incentive programmes differ by service territory. Budlong maintains teams across California so that local plan check experience sits behind every submission. More on how the practice is structured is on our company story page.

Sectors where the checklist changes shape

Healthcare adds a second review track and competing ventilation mandates. Education meets the new multi zone heat pump baseline head on and adds DSA review. Multifamily absorbs central domestic hot water electrification. Commercial buildings hit the photovoltaic and battery obligations first and hardest.

11. Related Reading

12. Frequently Asked Questions