Published: 25 Oct 2026 · Last verified: 25 Oct 2026 · Next review: Jan 2027 Cost figures are re-checked against permit records quarterly. Changes are logged in Corrections.
Chula Vista prices ADU permits like a menu, not a formula. Every other city in this series runs the building permit through a valuation schedule — dollars per thousand of assumed construction value, then plan-check percentages on top of that. Chula Vista’s Fee Bulletin 10-400 just says: detached ADU, standard plan, $3,951. That is $476 intake + $533 plan check + $2,942 inspection, published in one line, no math required. It is the only flat-rate ADU permit in the series, and the most transparently priced permit we have published.
The flat rate pairs with the 12 pre-approved City Standard ADU Plans the city built with SnapADU — every one already through plan check. Use one of those plans and the permit is $3,951; draw your own detached design and it is $4,963, also flat. The menu tells you exactly what each choice costs before you start.
Our six-phase total lands at $308,000, or $385 per square foot — well under the LA County baseline, though with honest gaps: the DIF dollar amount (proportional to the primary residence, with no published base figure) and ADU sewer/water capacity charges are marked “verify with city” and excluded from the total. The school fee is only half confirmed — the high-school district’s $3.01 rate is verified, the elementary district’s rate could not be found. Construction phases 2–6 are carried from the Los Angeles County baseline; Chula Vista does not publish phase-level construction costs.
The short answer
| 800 sq ft detached ADU · Chula Vista · 2026 | Amount |
|---|---|
| Total build cost (see assumptions) | $308,000 |
| Cost per square foot | $385 |
| Largest single line | Systems + interior, $147,000 |
| Building permit (flat, standard plan) | $3,951 (no valuation math) |
| DIF — pro-rata to primary residence | not counted (verify with city) |
| School fee (Sweetwater Union HSD only) | $2,408 (elementary district not found) |
| Sewer / water capacity charges | not counted (verify with city) |
The full line-item breakdown
Six phases. The same six used on every build in this series.
| Phase | Cost | Share |
|---|---|---|
| Soft costs (design, permits, fees) | $20,000 | 7% |
| Site work + foundation | $38,000 | 12% |
| Framing + structure | $48,000 | 16% |
| Building envelope | $42,000 | 14% |
| Systems + interior | $147,000 | 47% |
| Landscaping & hardscape | $13,000 | 4% |
| Total | $308,000 | $385 / sq ft |
The fee autopsy
Every fee line we found, with exactly what it is and where it came from.
| Fee line | Amount | Source / status |
|---|---|---|
| Design & engineering | $14,000 | Series baseline, carried (12 City Standard ADU Plans via SnapADU are an alternative — each already through plan check) |
| Building permit — Detached, Standard (All Plans) | $3,951 | $476 intake + $533 plan check + $2,942 inspection — Fee Bulletin 10-400, Master Fee Schedule (September 2024). “Standard” = using a City Standard Plan |
| Building permit — Detached, Nonstandard (custom, up to 1,200 SF) | $4,963 | $546 + $1,475 + $2,942 — same bulletin. Attached 1st-story 800 SF would be $3,226 ($2,380 first 300 SF + $423 × 2) |
| DIF — ADU 750 SF or larger | not counted | Charged “proportionately to the primary residence, on a square footage basis” — Fee Bulletin 16-100 (October 2025). ADUs under 750 SF and JADUs are fully exempt. Base dwelling fee amount not published — verify with city |
| School fee (Sweetwater Union HSD) | $2,408 | $3.01/sq ft × 800 — effective 2026-06-22 (April 20, 2026 board hearing). Residential room additions/conversions rate |
| School fee (Chula Vista Elementary SD, K–6) | not counted | Could not be found — no published $/sq ft rate or resolution on the CVESD site; developers’-fees fund mentioned only in budget documents. Verify with city |
| City sewer capacity charge | not counted | $5,072 per EDU confirmed (Fee Bulletin 12-100, October 2025; single-family = 1.00 EDU) — but whether a new EDU applies to an ADU is not stated in the schedule. Verify with city |
| Water capacity charge (Otay Water District etc.) | not counted | Could not be found — only an outdated 2014 Otay rate table surfaced; water service varies by district (Sweetwater Authority / California American / Otay Water). Verify with city |
The flat-rate permit: the series standout
In every other city we have published, the building permit is a function of valuation — the city assumes what the project costs, then applies a fee tier. Torrance’s flat-rate DIF ($2,243.47) was a series first for impact fees; Chula Vista does the same trick for the permit itself. $3,951 for a detached ADU on a Standard Plan, $4,963 for a custom detached design, and tiered per-300-SF pricing for attached units — all flat, all printed in the bulletin. No one has to guess the valuation.
The practical effect is budget certainty at the counter. A homeowner walks in with a chosen Standard Plan and knows the permit line to the dollar before filing. Compare that with Burbank’s valuation-based permit (the series’ most expensive permit-plus-plan-check at $3,692) or Long Beach’s DIF uncertainty, and Chula Vista’s approach reads as deliberate: pair pre-approved plans with a flat permit to pull friction out of the process.
The 750 sq ft cliff: proportional, not flat
Under 750 square feet, Chula Vista’s DIF treatment is simple — total exemption for the ADU and any JADU, straight from Fee Bulletin 16-100 (October 2025). At 750 and above, the city charges the ADU proportionally to the primary residence by square footage: the legal formula is published, but the city does not publish the base dwelling fee it multiplies against, so there is no dollar figure we could verify. Our 800 sq ft example crosses the cliff and would owe proportional DIF — we show the formula and the exemption boundary, not a number, and excluded it from the total. This is one of the items to settle with the city.
$2,408: the half-confirmed school fee
The Sweetwater Union High School District rate is solid — $3.01 per square foot, effective June 22, 2026 after an April 20, 2026 board hearing, published on the district’s own developer-fees page. On 800 sq ft that is $2,408. (Within part of Sweetwater’s boundary, the San Ysidro High School area uses $2.10 per square foot instead.)
The gap is the other half of the student’s life: the Chula Vista Elementary School District (K–6). We could not find any published developer-fee rate for CVESD — no dollar-per-square-foot figure, no adopted resolution. That means $2,408 is a floor, not a total: the true school fee for an ADU in Chula Vista may be higher once the elementary portion is added. Until we have the CVESD number, the fee autopsy carries an explicit blank.
Pre-approved plans that make the flat permit real
Twelve City Standard ADU Plans — six designs plus their mirror images — built with SnapADU, each already through plan check for code compliance. This is the most plans offered pre-approved in the series (Garden Grove’s ADU Go and Anaheim’s ADU Express each offer four), and it is load-bearing for the fee story: the $3,951 flat permit is specifically the “Standard (All Plans)” rate, unlocked by using one of these designs. A custom detached design is $4,963, still flat, still published. Design cost itself stays at the series baseline $14,000 — the free plans are the alternative, not the assumption.
Sewer and water: the blanks we could not fill
Two hard numbers exist and one useful absence does not. The City’s sewer capacity charge is confirmed at $5,072 per EDU (Fee Bulletin 12-100, October 2025) — but the schedule never says whether an ADU triggers a new EDU, so the application is unconfirmed. For water, there is nothing current at all: only a 2014 Otay Water District rate table surfaced, and service areas split between Sweetwater Authority, California American, and Otay Water depending on the address. Both lines are excluded from the total and marked “verify with city.”
Chula Vista vs. Los Angeles County
| Chula Vista | LA County baseline | |
|---|---|---|
| Total | $308,000 | $320,000 |
| Per sq ft | $385 | $400 |
| Building permit + plan check | $3,951 flat (most transparent) | carried |
| DIF | pro-rata to house — amount not published | carried |
| School fee | $2,408 (Sweetwater HSD only; CVESD not found) | $4,304 |
| Sewer capacity charge | $5,072/EDU confirmed, ADU application unconfirmed | carried |
| Water connection | not found (district-dependent) | carried |
| Pre-approved ADU plans | 12, free (SnapADU partnership) | none |
The $12,000 gap to the baseline comes mostly from soft costs: a flat $3,951 permit that needs no valuation, and a school fee that counts only the high-school district’s confirmed $2,408. The honest caveat is the size of the excluded unknowns — proportional DIF, the elementary school fee, and sewer/water capacity charges are all “verify with city,” and they push in one direction. The menu is the most transparent in the series; the total is the least complete.
A note on SB 1117
Signed September 2026, effective January 2027: for a homeowner’s first two ADUs, impact fees may apply only to square footage above 750, calculated marginally. Chula Vista’s proportional formula (“proportionally to the primary residence, on a square footage basis”) cannot survive that math unchanged — an 800 sq ft ADU would owe fees on 50 sq ft, not 800, which changes both the base and the ratio. We found no mention of SB 1117 in city materials; the January 2027 quarterly review will check for a revised fee bulletin. School fees are outside SB 1117’s impact-fee definition and stay at $2,408 plus whatever CVESD charges.
Disclaimer
Model estimate, not a quote. Fees change; the assumptions above are the city’s to confirm — the development impact fee amount, the elementary school district fee, the sewer EDU application to ADUs, and water district capacity charges are all marked where they appear. Always verify current fees with the City of Chula Vista Development Services Department before budgeting.