T24Studio
Tool · Title 24, Part 6

Does my project need a Title 24 report?

Three or four questions, answered against Section 150.2 and the CEC’s 2025 Single-Family Residential Compliance Manual. It runs in your browser, nothing is sent anywhere, and the rules it uses are written out underneath it.

Work it out

Check the scope against the code triggers

This runs entirely in your browser, and nothing is transmitted. Answer three or four questions and it tells you whether the permit needs a Title 24 report, which certificate of compliance it lands on, and the code section it comes from. The rules underneath it are written out in full below, so the tool is a shortcut rather than a black box.

If that panel does not appear, JavaScript is switched off — the same rules are written out immediately below, and they are the whole of the tool.

The rules the tool uses

All of it comes from two places: Title 24, Part 6 itself, and the CEC’s 2025 Single-Family Residential Compliance Manual, Chapter 9, which is the chapter on additions, alterations and repairs. The definitions are in Section 100.1 and the triggers in Section 150.2.

The workWhat the code calls itReportWhere it comes from
New home, or a detached ADUNewly constructed buildingCF1R — performance CF1R-PRF-01-E, or prescriptive CF1R-NCB-01-E§100.0, §150.0, §150.1
Addition, attached ADU, garage conversion, enclosed patioAddition — a change that increases both conditioned floor area and conditioned volumeCF1R — CF1R-ADD-01-E at 1,000 sf or less, CF1R-NCB-01-E above that, or performance§100.1 definition, §150.2(a)
Reroof, window replacement, added insulation, new ducts, furnace, AC, heat pump, water heaterAlteration — a change to a water-heating, space-conditioning, lighting system or envelope that is not an additionCF1R — CF1R-ALT-01-E, -02-E or -05-E, or performance§100.1 definition, §150.2(b)
Loft added inside existing volumeAlteration, not an addition — floor area increases but conditioned volume does notCF1R, on whichever components are alteredManual Example 9-3
Interior remodel with no envelope, HVAC or water-heating workStill an alteration, but nothing that triggers a certificate of complianceProbably none — mandatory measures still apply§110.1 appliances, §150.0(k) lighting; manual Example 9-2
Unconditioned addition — a sunroom with no heating or cooling, closed off from the houseUnconditioned space, so the envelope and mechanical requirements do not reach itLighting requirements still apply§100.0(c)2, §150.0(k); manual Example 9-1
RepairNot coveredNoneManual Chapter 9 overview
Commercial, retail, office, industrial, hotel, tenant improvementNonresidential — new construction, addition or alterationNRCC certificates of compliance, one per system2025 Nonresidential Compliance Manual
Three or more dwelling units, low riseLow-rise multifamilyLMCC certificates of compliance2025 Multifamily forms

The permit application date, not the start of construction, fixes the code cycle. Applications filed on or after January 1, 2026 are documented to the 2025 Energy Code.

The line that decides most of it

Chapter 9 of the manual states the trigger in one sentence: when additions and alterations include changes to the building envelope, mechanical systems, and/or water heating systems, a certificate of compliance form (CF1R) must be completed and submitted with the building permit application. That is the whole test for existing buildings. Everything else in the tool is working out which form.

Two definitions do the heavy lifting. An addition increases both conditioned floor area and conditioned volume — which is why a bay window that runs floor to ceiling is an addition and a loft inside an existing vaulted ceiling is not. An alteration is any change to a water-heating system, space-conditioning system, lighting system or envelope that is not an addition. Conditioning a space that was not conditioned before — the garage conversion case — is an addition, not an alteration, because it adds both.

Where the tool says probably not

It never says no. There are two reasons for that. The first is that the code still applies even when no certificate of compliance is produced: an interior remodel with new fixtures is an alteration, and the manual’s own worked example concludes that it “must comply only with the applicable mandatory requirements described in Section 110.1 for appliances and Section 150.0(k) for residential lighting.” Mandatory measures are not the same as no obligation.

The second is that the building department, not the code text, decides what lands on the counter. Some cities ask for an energy document on permits the state would not require one for; some name the form directly on an over-the-counter path, as Huntington Beach does on furnace and AC change-outs. Local plan-check practice varies more than the code does. So the honest output is “probably not, confirm with the city,” and if you want a second opinion the look is free.

Where the ADU cases land

The Energy Code has no definition of an accessory dwelling unit, so the manual classifies an ADU by what is physically being built. Detached with no shared walls is a newly constructed residential building. Attached to the house, or built over an existing detached garage, is an addition. Created inside existing conditioned space out of existing, altered and new components is an alteration. A JADU, which the code does define, is capped at 500 square feet and contained entirely within a single-family building. All four routes still produce a CF1R; they just start from different baselines, which is why the same ADU drawing can carry very different measures on two different lots.

Rates

Prices

Flat fees, in writing before I start. No hourly, no bid package, no change-order games — the number on the quote is the number on the invoice.

New client offer

Your first report with me

$150$9924–48 hours

One per client, homes under 3,000 square feet. Full energy model, CF1R and CHEERS registration. It’s a test run — send one job and see how it goes.

Every model after the first

$150Per model

The standard rate once you’re a client — the second building, ADU plus main house, the next project that walks in. Back in 3 business days.

Over 3,000 square feet

QUOTED

Quoted from the plans before any work starts, same day.

24×36 plan-sheet set

$20

Your CF1R laid out full size, matched to your drawing set. Comes back as a PDF you drop straight in.

Revisions

FREEFirst two

Two revisions included, plus questions any time. Past two I quote first, before I touch it.

Commercial / tenant improvement

QUOTEDSame day

Send the plans and you’ll have a flat quote back the same day. No deposit, no minimum.

Disclosure

One honest note

I’m not a licensed engineer or architect, and I don’t stamp drawings. On the CF1R I’m the documentation author — you stay the responsible designer. Nothing about your role on the job changes.

That’s on purpose. I’m not after your scope or your clients. I do one piece of the permit set — the piece that usually holds it up — and I do it fast.

Questions

Questions about the trigger

If yours isn’t here, see the full FAQ or call and ask.

What actually triggers a Title 24 report on an existing building?

One sentence in the CEC’s 2025 Single-Family Residential Compliance Manual carries most of it: when additions and alterations include changes to the building envelope, mechanical systems, and/or water heating systems, a CF1R must be completed and submitted with the building permit application.

So the question is not how big the job is or what it costs. It is whether the scope reaches the envelope, the space-conditioning system or the water heating. A reroof does. A kitchen refit with no window and no equipment change usually does not.

What is the difference between an addition and an alteration?

An addition increases both conditioned floor area and conditioned volume — Section 100.1. An alteration is any change to a water-heating system, space-conditioning system, lighting system or envelope that is not an addition.

The manual’s own example: add a loft inside an existing vaulted ceiling and floor area goes up but volume does not, so it is an alteration. Convert a garage to living space and both go up, so it is an addition. That distinction changes which forms and which prescriptive allowances apply, which is why the tool asks.

Does a small interior remodel need anything at all?

It is still an alteration under the code, but with no envelope, mechanical or water-heating work there is generally no certificate of compliance to produce. The mandatory measures do not go away: Section 110.1 for appliances and Section 150.0(k) for residential lighting still apply, and hardwired lighting changes are themselves listed as alterations.

Confirm with the building department before you submit without a report. Cities differ on what they ask for, and it is cheaper to ask than to answer a correction.

Does the tool work for commercial projects?

It routes them, but it does not go deep. Nonresidential and hotel work documents on NRCC forms rather than a CF1R, one certificate per system — envelope, mechanical, indoor and outdoor lighting, sign lighting, electrical power distribution, water heating, covered processes.

A lighting-only tenant improvement still produces an indoor lighting certificate of compliance. Low-rise multifamily of three or more units runs on the LMCC family instead.

Which code cycle applies to my project?

The permit application date sets it, not the start of construction and not the design date. Applications filed on or after January 1, 2026 are documented to the 2025 Energy Code; earlier live applications stay on the 2022 code.

That is why the tool asks for the date, and it is worth checking against the plan set you were handed — a pre-approved or standard plan drawn to the 2022 cycle does not carry over. The 2025 changes page has the before-and-after values.

The tool says probably not. Can I skip the report?

Treat it as a strong hint, not a clearance. The code text and the building counter are two different things: some cities ask for an energy document on permits the state would not require one for, and some name the form on an over-the-counter path. Ask the plan checker, and quote the scope rather than the conclusion.

If it is borderline, send the plans anyway. Looking at a scope and telling you it needs nothing costs nothing, and it is a faster answer than a correction notice six weeks later.

Not sure which way it falls?

Send the plan set. If the scope does not need a report I will say so and there is no charge for the look; if it does, you get the registered CF1R back with you named as responsible designer.