Published: 16 Oct 2026 · Last verified: 9 Oct 2026 · Next review: Jan 2027 Cost figures are re-checked against permit records quarterly. Changes are logged in Corrections.
Every city in this series has a 750 sq ft cliff — except the ones that deleted the cliff entirely. Salinas is the first: $0 in development and traffic impact fees on ADUs, at any size. Not reduced, not pro-rated, not deferred to 2027. Zero, by written city policy, published on the city’s official ADU page.
That single policy decision rearranges the entire fee picture. There is no 749-vs-800 optimization to run, no pro-rata math against the primary dwelling, no SB 1117 countdown that matters — the law arriving January 2027 changes nothing in Salinas, because there was never a cliff to remove. Our 800 sq ft benchmark lands at about $316,000, or $395 per square foot, and the money sits in different lines than anywhere else we have published.
The short answer
| 800 sq ft detached ADU · Salinas · 2026 | Amount |
|---|---|
| Total build cost (see assumptions) | ~$316,000 |
| Cost per square foot | ~$395 |
| Largest single line | Systems + interior, $147,000 |
| Building permit + plan check | ~$6,226 (valuation-based) |
| DIF — development + traffic | $0 (city policy) |
| School district fee (SUHSD) | $4,136 |
| Sewer capacity | $0 (ADU exempt by state law)* |
| Water connection | Not found |
| Free pre-approved plans | 4 designs |
| 750 sq ft cliff | None — no DIF on ADUs |
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) | ~$28,000 | 9% |
| Site work + foundation | $38,000 | 12% |
| Framing + structure | $48,000 | 15% |
| Building envelope | $42,000 | 13% |
| Systems + interior | $147,000 | 47% |
| Landscaping & hardscape | $13,000 | 4% |
| Total | ~$316,000 | ~$395 / 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 — free city plans reduce but don’t eliminate site-specific costs |
| Building permit (valuation) | $2,052 | $1,793 + 37 × $7 — FY 2026/27 fee schedule, $100,001–$500,000 tier |
| Combination permit | $3,078 | 150% of BPF (mechanical/electrical/plumbing included) — same schedule |
| Plan check | $1,847 | 90% of BPF — same schedule |
| General Plan maintenance | $1,004 | $7.35 per $1,000 valuation — Planning fee schedule |
| Technology surcharge | ~$295 | 5% — same schedule |
| Valuation basis | $136,640* | 800 × $170.80 (R-3 Type VB) — our assumption, varies by construction type |
| DIF — development + traffic | $0 | “City of Salinas does not charge development or traffic impact fees for ADU’s” — official ADU page |
| School fee (SUHSD) | $4,136 | $5.17 × 800 — Res 25-98 (Level II applicability unconfirmed) |
| Sewer (M1W capacity) | $0* | $6,093.55/unit exists but state law bars ADU capacity charges — exempt |
| Water (Cal Water) | Not found | No ADU-specific connection fee found |
The valuation trap
Salinas’s permit is valuation-based, and valuation is where the honest uncertainty lives. Our $6,226 example uses the Building Valuation Data table’s R-3 Type VB rate ($170.80/sq ft → $136,640 valuation). Change the construction type and the valuation — and every fee derived from it — moves. A heavier build (Type III) raises the permit; the city, not this post, sets your valuation. Budget the permit as a range, not a number.
The city’s own pre-approved plans hint at the workaround: two of the four designs (749 and 746 sq ft) sit just under 750. The cliff is meaningless for DIF in Salinas — but the permit tiers and the school-fee math still reward smaller footprints, and the plan drawers knew it.
Against the series baseline
| Salinas | LA County baseline | |
|---|---|---|
| Total | ~$316,000 | $320,000 |
| Per sq ft | ~$395 | $400 |
| Building permit + plan check | ~$6,226 (valuation) | carried |
| DIF | $0 (waived) | carried |
| School fee | $4,136 ($5.17) | $4,304 |
| Sewer capacity charge | $0* (exempt) | carried |
| Free pre-approved plans | 4 designs | none |
| 750 sq ft cliff | None | — |
Salinas lands $4,000 under the baseline with a completely different composition: the $0 DIF saves up to $10,000 against Anaheim-style cities, then hands about $6,200 back on the valuation-based permit. It is the clearest demonstration in the series that the cliff is a policy choice — and that deleting it does not make ADUs free, it just moves the money to lines the city still controls.
A note on SB 1117
Signed September 2026, effective January 2027: marginal impact fees above 750 sq ft. In Salinas, the marginal rate applies to a $0 base — nothing changes. School fees ($4,136) are outside SB 1117 and unchanged.
Disclaimer
Model estimate, not a quote. Fees change; the assumptions above are the city’s to confirm — the valuation basis, the school district’s current collection rate, and water connection fees are all marked where they appear. Always verify current fees with the City of Salinas before budgeting.