A California C-35 Lathing and Plastering license authorizes a contractor to apply wet-mixed coatings — traditional sand-and-cement stucco, gypsum plaster, or lime plaster — to exterior and interior surfaces, and to install the metal or wood lath and framing that those coatings adhere to. Under 16 CCR §832.35, a C-35 contractor “coats surfaces with a mixture of sand, gypsum plaster, quick-lime or hydrated lime and water, or sand and cement and water… applied with a plasterer’s trowel or sprayed over any surface which offers a mechanical means for the support of such coating, and will adhere by suction,” and also “applies and affixes wood and metal lath… to provide key or suction bases for the support of plaster coatings,” including the channel work and metal studs for solid plaster partitions. In plain terms: if the material goes on wet and is troweled or sprayed, and the surface needs lath or a mechanical key to hold it, that’s C-35 work.
What a C-35 License Covers: Scope of Work
The regulatory language covers a wide range of real jobs. Common C-35 project types include:
- New-construction exterior stucco — installing weather-resistive barrier, metal lath, and a three-coat (scratch, brown, finish) Portland cement plaster system on a new production or custom home.
- Stucco repair and patching — cutting out cracked or water-damaged sections, re-lathing, and color-matching a new finish coat to an existing wall.
- Interior wet-plaster walls and ceilings — traditional three-coat gypsum or lime plaster over metal or wood lath, still specified on higher-end and historic residential work.
- Veneer plaster systems — thin, one- or two-coat gypsum veneer plaster applied over special veneer-base panels, common in commercial tenant improvements.
- Solid plaster partitions and soundproofing/fireproofing coatings — the CCR definition specifically calls out coatings applied for soundproofing and fireproofing purposes, not just decorative finish.
- Historic plaster restoration — matching lime-plaster mixes and lath techniques on older buildings where modern cement stucco isn’t appropriate.
A note on EIFS (synthetic stucco): C-35 contractors commonly install EIFS (foam board plus a polymer-modified base and finish coat) since the finish coat is troweled on much like traditional stucco. But CSLB has not published a classification opinion placing EIFS explicitly inside or outside 16 CCR §832.35, and manufacturers like Dryvit and Parex often require their own installer certification separate from any state license. Treat EIFS as a gray area: confirm manufacturer certification requirements per project rather than assuming a C-35 alone covers it.
The C-35 Trade Exam: Content Outline and Structure
CSLB’s official Lathing and Plastering (C-35) study guide (effective for exams scheduled on or after October 1, 2025) publishes this content outline, broken into five sections:
- Planning and Estimating — 15% (interpreting plans and specifications, estimating material/equipment/labor, inspecting job sites)
- Lath Preparation and Installation — 20% (coordinating lath and plaster installation, preparing substrates, installing metal framing and gypsum systems, installing lathing materials, sealing penetrations)
- Plaster/Stucco Preparation and Installation — 28% (mixing and applying scratch and brown coats, installing plaster/stucco systems, installing specialty plaster/stucco, job-site cleanup)
- Repairs — 17% (repairing plaster/stucco installations)
- Safety — 20% (personnel and job-site safety, Cal/OSHA laws and regulations, personal protective equipment)
CSLB labels these percentages “approximate.” The exam is closed-book, multiple choice with four options per question, includes math computation (a calculator is provided), and has no penalty for guessing. Every C-35 candidate also sits for the separate Law and Business exam required of all CSLB applicants. CSLB’s published study guide does not state an exact total question count, time limit, or numeric passing score for the C-35 trade exam — third-party prep sites publish estimates, but since CSLB itself doesn’t confirm them, we won’t repeat unverified numbers here. Listed reference materials include the current California Building Code and Residential Code (Title 24), the Builder’s Guide to Stucco, Lath & Plaster, the Gypsum Construction Handbook, the Portland Cement Plaster/Stucco Manual, and Title 8 Cal/OSHA safety orders.
C-35 License Requirements: Experience, Bond, and Fees
- Experience: Four years of journey-level lathing/plastering experience within the past 10 years, as a journeyman, foreman, supervising employee, or contractor. CSLB may credit up to three of those four years for verified education or apprenticeship training (a board-wide rule, not C-35-specific), but at least one year must be hands-on.
- Contractor bond: $25,000, the statewide minimum since Senate Bill 607 raised it from $15,000 effective January 1, 2023.
- Bond of Qualifying Individual (BQI): An additional $25,000 bond when the qualifier is a Responsible Managing Employee (RME), or an RMO/RMM/RM owning less than 10% of the company.
- Fees: A nonrefundable $450 application fee, plus an initial license fee of $200 (sole ownership) or $350 (all other business types) after passing both exams.
- Live Scan fingerprinting: Required for every original CSLB application, C-35 included.
- Workers’ compensation: C-35 is not among the five classifications CSLB currently bars from a no-employee workers’ comp exemption — that list is limited to C-8, C-20, C-22, C-39, and D-49 under SB 216. SB 1455 delayed the broader phase-out of the no-employee exemption for all remaining classifications, C-35 included, to January 1, 2028.
- Small-job exemption: Under AB 2622 (effective January 1, 2025), unlicensed work under $1,000 with no permit and no hired workers is exempt — a narrow carve-out, not a substitute for licensure on real jobs.
How C-35 Differs From C-9, C-29, and C-8
Classification boundaries in CSLB’s code trip up a lot of applicants, and the C-35 lines are some of the more literal ones in the whole classification list, because they hinge on whether a material is wet or dry, and applied or embedded.
C-35 vs. C-9 (Drywall)
Our C-9 guide frames the split this way: “C-9 covers dry gypsum board joined with tape and joint compound. Stucco exterior needs C-35; interior drywall needs C-9.” That’s the correct rule, and it holds up under 16 CCR §832.35 and §832.09 — C-9 installs and finishes solid gypsum wallboard panels with tape and joint compound; C-35 mixes and troughs on a wet material (plaster or stucco) over lath. A wall finished in taped, mudded drywall is C-9 work. The same wall finished in troweled veneer plaster over a lath or veneer-plaster base is C-35 work, even though both can look similar once painted.
C-35 vs. C-29 (Masonry)
C-29 covers fabricating and installing masonry units — brick, block, and stone — for structural and non-structural walls, plus ceramic veneer, thin brick, paving, and incidental waterproofing/cleaning/caulking. When stucco or plaster is applied as a finish coat over a masonry wall, that finish-coat work is plastering, not masonry, and falls to C-35 — the masonry unit and the wet coating troweled over it sit under two different classification sections. A mason builds the block wall; a plasterer coats it.
C-35 vs. C-8 (Concrete)
This boundary is spelled out in the C-8 regulation itself. 16 CCR §832.08 defines C-8 as forming, pouring, placing, and finishing concrete, but explicitly excludes “contractors whose sole contracting business is the application of plaster coatings.” A contractor finishing a concrete slab operates under C-8; a contractor who then plasters or stuccos a wall operates under C-35 — CSLB drew this line directly in the regulatory text.
Who Needs a C-35 License?
C-35 fits stucco subcontractors on new-home tract and custom crews, standalone stucco repair/restoration companies (a growing niche as 1970s–2000s CA stucco stock needs re-coating or crack remediation), historic plaster restoration specialists, and EIFS/synthetic-stucco crews (subject to the manufacturer-certification caveat above). It’s also the classification a general (B) contractor’s plastering sub must hold, since a B license alone doesn’t authorize self-performing specialty plastering scope on most jobs.
Frequently Asked Questions
Does a C-35 license cover both interior plaster and exterior stucco?
Yes. 16 CCR §832.35 doesn’t distinguish interior from exterior — it covers any surface coated with sand/gypsum plaster, lime plaster, or sand-and-cement stucco troweled or sprayed over a lathed or suction-ready base.
Can a C-9 drywall contractor also install stucco?
No, not under C-9 alone. C-9 is limited to dry gypsum board systems joined with tape and joint compound. Wet-applied stucco requires C-35.
Is EIFS (synthetic stucco) definitely covered by C-35?
C-35 contractors commonly install EIFS, but CSLB hasn’t published an explicit classification ruling on it, and manufacturers often require their own installer certification. Confirm that separately per product.
How much experience do I need for a C-35 license?
Four years of journey-level lathing/plastering experience within the past 10 years, with up to three years creditable via verified trade school or apprenticeship training (minimum one year must be hands-on).
What bond does a C-35 contractor need?
A $25,000 contractor bond (statewide minimum since SB 607, effective January 1, 2023), plus a separate $25,000 Bond of Qualifying Individual if the qualifier is an RME or a low-ownership RMO/RMM/RM.
Does a C-35 contractor need workers’ compensation insurance?
C-35 isn’t on CSLB’s current no-exemption list (C-8, C-20, C-22, C-39, D-49), so a genuinely employee-free C-35 licensee can still file a workers’ comp exemption today. SB 1455 pushed the statewide requirement for all classifications to January 1, 2028.
What percentage of the C-35 exam covers safety?
CSLB’s study guide lists Safety at 20%, tied with Lath Preparation and Installation as the second-largest content area behind Plaster/Stucco Preparation and Installation at 28%.
Can I legally do small stucco patch jobs without a C-35 license?
Only under AB 2622’s exemption: total job price under $1,000, no permit required, and no hired workers. Anything larger or permit-requiring needs a licensed C-35 contractor.
Not sure C-35 is the right fit, or juggling it against a C-9 or C-29 scope question on your own project list? Start at Find Your Classification to confirm the correct license before you invest study time. Once you know your classification, our exam prep builds a study plan around CSLB’s actual published content outline instead of generic trade trivia. New to how the process works end to end? How It Works walks through study guide, practice exams, and Law & Business prep together. Compare study packages on Pricing, or if your classification question is more nuanced than this page covers, contact us directly.