Solar Installation — Washington license requirements
01 The project
The starting point is the work itself — Solar Installation in Washington. The job determines which trades are involved, and the trades determine which license classifications may be required.
| Component | Trade |
|---|---|
| Solar energy system | Solar |
| Electrical interconnection | Electrical |
02 Jurisdiction
This project is evaluated for Washington — the registration-plus-trade-credential state. Construction contractors hold the ch. 18.27 contractor registration (no exam, $30k/$15k bond by class), while electrical (ch. 19.28) and plumbing (ch. 18.106) run through their own contractor licences and certified individuals under L&I. The $500 and $2,000 bands decide small jobs, RCW 18.27.130 preempts local contractor licences, and RCW 18.27.110 makes the local permit issuer verify the registration. Washington jurisdiction page.
Permit fees, plan-review timelines and every locality beyond Seattle, Spokane, Tacoma, Vancouver and Bellevue remain LOCAL_AUTHORITY_REQUIRED; Spokane was researched from search-result snippets and its official PDF, a disclosed limitation. The statewide electrical work-permit fee schedule is NOT_VERIFIED. Without a job-site location the local permit answer is NOT_DETERMINED, never a guess. State requirements are not the complete story for any locality.
03 Trade → license
Relations below are recorded per state — only this jurisdiction's classifications are shown.
Trades involved: Solar, Electrical.
- May require ELECTRICAL-CONTRACTOR-GENERAL-01 — General Electrical Contractor License (01) (business) confirmed S-WA-WAC-296-46B-920 rule WA-SOLAR-CREDENTIALThe default answer: rooftop PV is electrical construction work → electrical contractor license (general 01 covers 'all phases and all types') + certified electricians. There is NO generic 'solar contractor license' in Washington — verified absence (no solar entry among the 63 WAC specialties; REQ-WA-NO-SOLAR-LICENSE-001). Permit: local electrical permit — Seattle: PV <7.7 kW online without plan review (research §N.6/§O).
- Alternative path ELECTRICAL-RESIDENTIAL-02 — Residential (02) Electrical Specialty (license/certificate scope) reported S-WA-WAC-296-46B-920 rule WA-ELEC-02-SOLARThe OPEN question: WAC 296-46B-920(2)(a)(ii)(D) excludes from residential (02) 'interconnected electric power production sources not connected to equipment that supplies one- and two-family dwellings …' — the rooftop-PV-in-dwelling reading is genuinely ambiguous (SCOPE-WA-ELEC-02-SOLAR), so the rule WA-ELEC-02-SOLAR answers NOT_DETERMINED for (02) while (01) is positive. Never resolved by assumption (research quality gate §22).
- Component basis ELECTRICIAN-JOURNEY-01 — General Journey Level Electrician (01) (individual certificate) confirmed S-WA-LNI-ELECTRICIAN rule WA-ELEC-WORKERThe worker limb: certified electricians (journey 01 or specialty categories) install; trainees supervised (75%/100% by class). L&I inspects statewide under RCW 19.28.101 (48 h on request; utility connects only after approval) except local enforcement under RCW 19.28.141 (Seattle) (research §N.6).
- Alternative path SPECIALTY-HVAC-R — Heating, Ventilation, Air-Conditioning and Refrigeration (HVAC/R) (specialty) confirmed S-WA-WAC-296-200A-016 rule WA-SOLAR-CREDENTIALSolar THERMAL (hot-water/space heating) limb: inside the HVAC/R specialty — WAC 296-200A-016(28) includes 'systems that utilize solar energy' — and boiler/process-piping specialty (4) for associated solar heating equipment. Not an electrical 'solar license' question at all (research §O.2).
04 Scope
What the official sources say about the work involved — typed assertions, never a boolean "covers". Interpretations are marked as such.
- Officially excluded SPECIALTY-HVAC-R Line Voltage Controllers Or Disconnects External To Hvac Equipment (may_not_perform) WAC 296-46B-920(2)(f) S-WA-WAC-296-46B-920 The external-electrical boundary for HVAC replacement: line-voltage work outside the unit is ELECTRICAL contracting, not HVAC specialty work (research §N.4).
- Officially included SPECIALTY-HVAC-R Heating Ventilating Air Conditioning Systems And Attached Services (may_perform) WAC 296-200A-016(28) S-WA-WAC-296-200A-016 HVAC's whole statewide answer: a registration specialty, not a license — plus the external-electrical boundary in SCOPE-WA-HVAC-NO-EXTERNAL-DISCONNECT (research §10/§N.4).
- Officially included ELECTRICAL-CONTRACTOR-GENERAL-01 All Phases And All Types Of Electrical And Telecommunications Installations (may_perform) WAC 296-46B-920(1); RCW 19.28.041 S-WA-WAC-296-46B-920 The unambiguous electrical credential — general (01) is the one qualified for rooftop PV without interpretive strain (research §D.3/§O).
05 Requirements
| Requirement | Kind | Statement | Source |
|---|---|---|---|
| NO solar contractor license or solar specialty — PV work runs on the ELECTRICAL credential; residential (02) scope has an express PV boundary 63-specialty enumeration + WAC 296-46B-920(2)(a)(ii)(D) + Seattle Electrical Permit (read 2026-10-04) | license | Verified by enumerating all 63 WAC 296-200A-016 specialties (read in full 2026-10-04): no solar classification exists; solar-related scope appears only inside HVAC/R (28, 'systems that utilize solar energy') and boiler/steam/process piping (4, 'solar heating equipment associated with these systems'). Photovoltaic installation is 'electrical construction trade' work → electrical contractor license (general 01 = 'all phases and all types,' unambiguously qualified). The residential (02) specialty's WAC scope EXCLUDES '(D) Interconnected electric power production sources not connected to equipment that supplies one- and two-family dwellings, or multifamily dwellings of types III, IV or V construction, or ancillary structures' — whether 02 may install rooftop PV tied to the dwelling's own equipment is genuinely ambiguous. Seattle: 'If your solar PV system is rated under 7.7KW, you can apply online without plan review. However, you must have your plans and the manufacturer installation instructions available at the job site during your electrical inspection.' | S-WA-WAC-296-46B-920Source S-WA-WAC-296-46B-920 — Washington State Legislature — RCW & WAC (app.leg.wa.gov)WAC 296-46B-920 — Electrical/telecommunications license/certificate types and scope of work — 63-specialty enumeration + WAC 296-46B-920(2)(a)(ii)(D) + Seattle Electrical Permit (read 2026-10-04) https://app.leg.wa.gov/WAC/default.aspx?cite=296-46B-920 Retrieved 2026-10-04 · last verified 2026-10-04 Read in full 2026-10-04. (1) general electrical (01) 'encompasses all phases and all types of electrical and telecommunications installations and minor plumbing under RCW 18.106.150' (like-in-kind includes the appliance 'or any component part … e.g., the thermostat in a water heater'). (2) specialties may not do ch. 18.106 plumbing work EXCEPT residential (02) with the RCW 18.106.150 exceptions. (2)(a) residential (02): 1-2 family dwellings and MF types III/IV/V ≤6 stories, exclusions incl. '(ii)(D) Interconnected electric power production sources not connected to equipment that supplies one- and two-family dwellings, or multifamily dwellings of types III, IV or V construction, or ancillary structures' (the solar boundary — CONFLICT-adjacent, rule WA-ELEC-02-SOLAR answers NOT_DETERMINED). (2)(f) HVAC/refrigeration electrical specialties 06A/06B: may NOT install line-voltage controllers or disconnects external to HVAC equipment (narrow like-in-kind disconnect exception ≤20A/120V during equipment replacement) — the external-electrical boundary for HVAC work. Also defines 03/03A/04/06/07/07A/07B/07C/07D/07E/09/10 scopes. |
| Electrical contractor license required to engage in the electrical construction trade — UBI + designated master/administrator + $4,000 bond L&I Electrical Contractor page verbatim + RCW 19.28.041 (read 2026-10-04) | license | L&I (read verbatim 2026-10-04): 'To engage in the business of the electrical construction trade, you must get an electrical contractor license from L&I.' RCW 19.28.041: unlawful to do electrical contracting without the license; general (01) or specialty; expires 24 calendar months; application needs WC evidence, ESD number, excise tax registration and UBI; must designate an individual holding a valid master journey level / master specialty electrician or administrator certificate (19.28.041(5)); original $4,000 electrical/telecommunications contractor's surety bond (or assignment of savings), one bond maximum even with multiple specialty licenses, cancellation → suspension; '(4)' is EXCLUSIVE against political subdivisions — no local electrical licenses/bonds/fees for the same purpose. L&I: 'All work performed must be done by properly certified electricians.' 'If an electrical contracting business does other, non-electrical work, registration as a contractor may also be required.' | S-WA-LNI-ELEC-CONTRACTORSource S-WA-LNI-ELEC-CONTRACTOR — Washington State Department of Labor & Industries (L&I)L&I — Electrical Contractor (license requirements, bond, renewal, reinstatement) — L&I Electrical Contractor page verbatim + RCW 19.28.041 (read 2026-10-04) Retrieved 2026-10-04 · last verified 2026-10-04 Read in full 2026-10-04. Verbatim: 'To engage in the business of the electrical construction trade, you must get an electrical contractor license from L&I.' General electrical (01) = all types of electrical and telecommunications installations; specialty electrical contractors = WAC 296-46B-920(2) categories; 'All work performed must be done by properly certified electricians.' Requirements: valid UBI (DOR or SOS), a certified assigned electrical administrator or master electrician, an original $4,000 electrical/telecommunication contractor's surety bond (or assignment of savings), a workers' compensation account if the business hires employees. 'Electrical contractors are encouraged to carry general liability insurance. However, L&I does not keep records of liability insurance for electrical contractors.' 'If an electrical contracting business does other, non-electrical work, registration as a contractor may also be required.' Renew every 2 years (bond current, administrator assigned, no unpaid citations); >90 days expired → cannot renew online; suspension whenever requirements lapse; reinstatement with documents + fee (WAC $71.50); application F500-018-000; 8-10 week application processing; 12-digit license number. CONFLICT-WA-002 quote (side B) lives here. |
| Individual electrician certificate required to work in the electrical trade — journey (01) or one of 14 specialties, exam via PSI L&I Electrician page verbatim (read 2026-10-04) | license | L&I (read verbatim 2026-10-04): 'To work in the electrical construction trade in Washington, you must have a valid electrician certificate issued by L&I.' General journey level (01) = 'all types of electrical and telecommunications installations,' qualified with 8,000 hours (≤4,000 in 4,000-hour specialties) + 96 hours basic classroom instruction, then PSI exam; 14 specialty categories — 4,000-hour (Residential 02, Pump and irrigation 03, Signs 04, Limited energy 06, HVAC/refrigeration 06A, Nonresidential maintenance 07; trainees supervised ≥75%, 48 h classroom) and 2,000-hour (Domestic well 3A, HVAC restricted 6B, Nonres lighting/retrofit 7A, Residential maintenance 7B, Restricted nonres 7C, Appliance repair 7D, Equipment repair 7E, Door/gate 10; 100% supervision). Trainees 16+. Oregon reciprocity for (01). | S-WA-LNI-ELECTRICIANSource S-WA-LNI-ELECTRICIAN — Washington State Department of Labor & Industries (L&I)L&I — Electrician (individual certificates, experience, exams, renewal, CE) — L&I Electrician page verbatim (read 2026-10-04) https://lni.wa.gov/licensing-permits/electrical/electrical-licensing-exams-education/electrician Retrieved 2026-10-04 · last verified 2026-10-04 Read in full 2026-10-04. 'To work in the electrical construction trade in Washington, you must have a valid electrician certificate issued by L&I.' Two levels: general journey level (01) 'may perform all types of electrical and telecommunications installations' — qualify with 8,000 hours (no more than 4,000 in 4,000-hour specialties) + 96 hours basic classroom instruction, then PSI exam; 'There are 14 specialty categories in the electrical construction trade' — 4,000-hour specialties Residential (02), Pump and irrigation (03), Signs (04), Limited energy (06), HVAC/refrigeration (06A), Nonresidential maintenance (07) (trainees supervised ≥75%, 48 h classroom); 2,000-hour specialties Domestic well (3A), HVAC restricted (6B), Nonresidential lighting maintenance/retrofit (7A), Residential maintenance (7B), Restricted nonresidential maintenance (7C), Appliance repair (7D), Equipment repair (7E), Door/gate/similar systems (10) (100% supervision until exam). Trainees 16+. Oregon reciprocity for (01). Renew every 3 YEARS on your birthday — 24 hours CE incl. 8 hours code update + 4 hours RCW/WAC; fee doubles after expiration; >90 days expired → retest only; inactive status while not working. Exams scheduled with PSI after approval (research §K). |
| OPEN CONFLICT — does an electrical-ONLY business need ch. 18.27 registration? L&I's two pages disagree (NOT_DETERMINED) L&I Electrical Contractor vs L&I Register pages + RCW 18.27.090/.18.106.400(3) (all read 2026-10-04) | registration | Side A — L&I Register-as-a-Contractor (official): 'Washington State requires ALL construction contractors to register with L&I,' with electrical listed among trades having 'additional requirements' on top of registration (implying registration PLUS the electrical license). Side B — L&I Electrical Contractor (official): 'If an electrical contracting business does other, non-electrical work, registration as a contractor MAY ALSO BE REQUIRED' (implying electrical-only businesses may not need it). Statute read: RCW 18.27.090 contains NO electrical-contractor exemption; RCW 19.28.041(4)'s exclusivity runs against political subdivisions, not ch. 18.27; yet the Legislature knows how to exempt a trade and did so for PLUMBING (RCW 18.106.400(3)) but NOT for electrical. No L&I erratum resolves it (CONFLICT-WA-002). | S-WA-LNI-ELEC-CONTRACTORSource S-WA-LNI-ELEC-CONTRACTOR — Washington State Department of Labor & Industries (L&I)L&I — Electrical Contractor (license requirements, bond, renewal, reinstatement) — L&I Electrical Contractor vs L&I Register pages + RCW 18.27.090/.18.106.400(3) (all read 2026-10-04) Retrieved 2026-10-04 · last verified 2026-10-04 Read in full 2026-10-04. Verbatim: 'To engage in the business of the electrical construction trade, you must get an electrical contractor license from L&I.' General electrical (01) = all types of electrical and telecommunications installations; specialty electrical contractors = WAC 296-46B-920(2) categories; 'All work performed must be done by properly certified electricians.' Requirements: valid UBI (DOR or SOS), a certified assigned electrical administrator or master electrician, an original $4,000 electrical/telecommunication contractor's surety bond (or assignment of savings), a workers' compensation account if the business hires employees. 'Electrical contractors are encouraged to carry general liability insurance. However, L&I does not keep records of liability insurance for electrical contractors.' 'If an electrical contracting business does other, non-electrical work, registration as a contractor may also be required.' Renew every 2 years (bond current, administrator assigned, no unpaid citations); >90 days expired → cannot renew online; suspension whenever requirements lapse; reinstatement with documents + fee (WAC $71.50); application F500-018-000; 8-10 week application processing; 12-digit license number. CONFLICT-WA-002 quote (side B) lives here. |
| Electrical permits — state L&I by default (permit affixed, inspection before utility connect), local enforcement where the city opts in RCW 19.28.101/.141 + Seattle Electrical Permit page (read 2026-10-04) | permit | RCW 19.28.101 (read in full 2026-10-04): L&I inspects all covered wiring; an electrical work permit is required (fees set by rule), the permit is affixed to the installation, and the utility may connect only after inspection approval; no wiring may be concealed before approval; inspections within 48 hours on request (24 hours for utility-connect cases). '(6) The director … shall set by rule a schedule of license and electrical work permit fees.' RCW 19.28.141 (noted in the section): a city/town enforcing an equal-or-higher standard exempts itself from state inspection within its limits, and localities are permitted — not required — to enforce state permitting/inspection standards. Seattle does: it issues electrical permits ('Any professional applying for electrical permits must have a Washington State electrical contractor's license and a Seattle business license') and performs cover/service/final inspections itself. | S-WA-19-28-101Source S-WA-19-28-101 — Washington State Legislature — RCW & WAC (app.leg.wa.gov)RCW 19.28.101 — Inspections — Permits, fees — Limitation — Waiver during state of emergency — RCW 19.28.101/.141 + Seattle Electrical Permit page (read 2026-10-04) https://app.leg.wa.gov/RCW/default.aspx?cite=19.28.101 Retrieved 2026-10-04 · last verified 2026-10-04 Read in full 2026-10-04: L&I inspects all covered wiring/appliances/devices/equipment (state default); electrical work permit required and affixed to the installation, utility connects only after approval; no wiring concealed before approval; inspections within 48 hours on request (24 h for utility-connect cases); '(6) The director … shall set by rule a schedule of license and electrical work permit fees' — the fee authority for WAC 296-46B-909 (amounts of the PERMIT schedule NOT_VERIFIED — research §L). Local opt-out: 'RCW 19.28.101 inapplicable in certain cities, towns, electricity supply agency service areas …: RCW 19.28.141' — the provision Seattle uses to issue and inspect its own electrical permits (research §B/§M.1). Backs REQ-WA-ELECTRICAL-PERMIT-001. |
| Seattle (SDCI) — $6,000/6-month no-permit band, re-roof exemption, city electrical permits, city business license (LOCAL EXAMPLE) Seattle Do-You-Need-a-Permit / Re-Roof / Electrical / Mechanical pages verbatim (read 2026-10-04) | permit | Seattle SDCI pages (all read 2026-10-04): 'You don't need a permit for minor repairs or alterations that cost $6,000 or less in any 6-month period … even if you do the work yourself' — but load-bearing/envelope/egress work always needs a permit. Re-roof: 'A permit is not required for re-roof work at one- and two-family homes and townhouses if no changes are made to the building envelope other than adding or replacing insulation…'; required when repairing >500 sq ft or replacing roofing materials on commercial/multifamily (or envelope changes); no on-site inspection, close by affidavit. Electrical permits: 'Any professional applying for electrical permits must have a Washington State electrical contractor's license and a Seattle business license. Property owners may do their own work when they own and occupy the property they're working on'; Seattle performs cover/service/final inspections (local enforcement under RCW 19.28.141); small solar PV <7.7 kW without plan review. Mechanical permits by value + hourly review; gas lines/plumbing are separate permits. Seattle business license required to do business in the city. NO local contractor license exists (RCW 18.27.130). | S-WA-SEATTLE-PERMITSource S-WA-SEATTLE-PERMIT — City of Seattle — Seattle Department of Construction and Inspections (SDCI)Seattle SDCI — Do You Need a Permit? ($6,000/6-month minor-work threshold, exemptions) — Seattle Do-You-Need-a-Permit / Re-Roof / Electrical / Mechanical pages verbatim (read 2026-10-04) https://www.seattle.gov/construction-and-inspections/permits/do-you-need-a-permit Retrieved 2026-10-04 · last verified 2026-10-04 LOCAL EXAMPLE — read 2026-10-04 (HTTP 200). Verbatim: 'Minor repairs or alterations. You don't need a permit for minor repairs or alterations that cost $6,000 or less in any 6-month period. The $6,000 limit is based on fair market value of labor and parts, even if you do the work yourself.' 'You need a permit for any work on load-bearing supports, changes to the building envelope, and work that reduces egress, light, ventilation, or fire resistance no matter how small the project.' Usually no permit: painting/cleaning, re-pointing a chimney, installing kitchen cabinets, paneling/surface finishes over existing systems, insulating existing buildings, hazardous-material abatement, limited in-kind repair; on-grade patios/slabs; sheds <120 sq ft; retaining walls ≤4 ft; fences <8 ft; platforms/walks/driveways <18 in. above grade; dish/panel antennas ≤6.56 ft. 'Even if you don't need a permit, your project must meet all code requirements.' Seattle Residential Code R105.2 / Building Code 106.2 referenced (research §M.1/§N.2). |
06 Rule: WA-SOLAR-CREDENTIAL
Verified absence: there is NO solar contractor license or solar specialty in Washington — no solar entry among the 63 WAC 296-200A-016 specialties and no solar chapter in RCW Title 18/19 read. Photovoltaic work = ELECTRICAL licensing: electrical contractor license (general (01) unambiguous; residential (02) boundary OPEN — rule WA-ELEC-02-SOLAR) with certified electricians. Solar THERMAL sits inside the HVAC/R specialty ('systems that utilize solar energy', WAC 296-200A-016(28)) and boiler/process-piping specialty (4). Missing facts yield NOT_DETERMINED.
| Outcome | Conclusion | Caveats |
|---|---|---|
| photovoltaic-is-electrical | no_solar_license_electrical_credential_required |
|
| solar-thermal-hvac | solar_thermal_under_hvac_specialty |
|
Rule confidence: confirmed. Missing inputs produce NOT_DETERMINED — never a forced answer. Sources: S-WA-WAC-296-46B-920S-WA-LNI-ELEC-CONTRACTORS-WA-WAC-296-200A-016
07 Rule: WA-ELEC-02-SOLAR
WAC 296-46B-920(2)(a)(ii)(D) verbatim excludes from the residential (02) specialty: 'Interconnected electric power production sources not connected to equipment that supplies one- and two-family dwellings, or multifamily dwellings of types III, IV or V construction, or ancillary structures'. Whether a residential (02) specialty contractor may install rooftop PV is GENUINELY AMBIGUOUS under this text (research quality gate — interpretation OPEN): one reading keeps PV feeding the dwelling service inside (02); another excludes PV arrays generally. General (01) is unambiguously qualified. This rule therefore answers NOT_DETERMINED for (02) unless a clarified scope fact is supplied. Missing facts yield NOT_DETERMINED.
| Outcome | Conclusion | Caveats |
|---|---|---|
| general-01-qualified | general_01_may_install_rooftop_pv |
|
| residential-02-with-clarified-scope | residential_02_may_install_rooftop_pv |
|
| residential-02-scope-excluded | residential_02_may_not_install_rooftop_pv |
|
| not-pv-work | not_a_photovoltaic_scope_question |
|
Rule confidence: reported. Missing inputs produce NOT_DETERMINED — never a forced answer. Sources: S-WA-WAC-296-46B-920
08 Rule: WA-ELEC-WORKER
L&I Electrician page verbatim: 'To work in the electrical construction trade in Washington, you must have a valid electrician certificate issued by L&I.' General journey level (01) qualifies with 8,000 hours (no more than 4,000 in 4,000-hour specialties) + 96 hours classroom then a PSI exam; 14 specialty categories on 4,000-hour and 2,000-hour paths; trainees 16+ must be supervised (75% or 100% by specialty class). Renewal every 3 years on your birthday with 24 hours CE. Missing facts yield NOT_DETERMINED.
| Outcome | Conclusion | Caveats |
|---|---|---|
| certificate-required | electrician_certificate_required |
|
| supervised-trainee | supervised_trainee_path |
|
| no-electrical-work | outside_electrical_trade |
|
Rule confidence: confirmed. Missing inputs produce NOT_DETERMINED — never a forced answer. Sources: S-WA-LNI-ELECTRICIANS-WA-19-28-041
09 Rule: WA-ELEC-CONTRACTOR
RCW 19.28.041: unlawful to do electrical contracting without an electrical contractor license — a SEPARATE credential from ch. 18.27 registration (general 01 or a WAC 296-46B-920(2) specialty), 24 calendar months, $4,000 surety bond (one maximum across specialties), UBI + WC evidence + excise registration on application, and a designated individual holding a valid master journey level / master specialty / administrator certificate. L&I: 'All work performed must be done by properly certified electricians.' Whether an electrical-only business must ALSO hold ch. 18.27 registration is CONFLICT-WA-002 (rule WA-ELEC-ONLY-REG). Missing facts yield NOT_DETERMINED.
| Outcome | Conclusion | Caveats |
|---|---|---|
| electrical-license-required | electrical_contractor_license_required |
|
| electrical-license-held | electrical_license_already_held |
|
| not-electrical-work | outside_electrical_regulation |
|
Rule confidence: confirmed. Missing inputs produce NOT_DETERMINED — never a forced answer. Sources: S-WA-19-28-041S-WA-LNI-ELEC-CONTRACTORS-WA-WAC-296-46B-920
10 No solar licence — electrical credential, an honest 01/02 question, one permit gate
Washington has NO generic "solar licence" (verified absence). A hired rooftop PV install is electrical work, and one part of the electrical question is genuinely open:
| Question | Washington answer | Source |
|---|---|---|
| Generic solar licence | none exists — the credential is electrical (rule WA-SOLAR-CREDENTIAL) | S-WA-WAC-296-46B-920 |
| Default credential path | an electrical contractor licence with a designated certified master/administrator and certified electricians (ch. 19.28; rule WA-ELEC-CONTRACTOR) | S-WA-LNI-ELEC-CONTRACTOR |
| May a residential (02) electrician do rooftop PV? | OPEN — WAC 296-46B-920(2)(a)(ii)(D) excludes interconnected power-production sources not connected to dwelling-supplying equipment; the rooftop-PV-in-a-dwelling reading is ambiguous and returns NOT_DETERMINED, while the general (01) class is unambiguous (rule WA-ELEC-02-SOLAR) | S-WA-LNI-ELECTRICIAN |
| Solar-thermal | runs through the HVAC/R (and boiler) specialties under the ch. 18.27 registration | S-WA-18-27-010 |
| Electrical-only business registration | whether an electrical-only business must also hold the ch. 18.27 registration is an OPEN conflict (CONFLICT-WA-002) and returns NOT_DETERMINED | S-WA-LNI-ELEC-CONTRACTOR |
| Permit and inspection | the electrical permit and inspection regime applies on top; Seattle publishes a small-system path (LOCAL example) | S-WA-19-28-101 |
The 01/02 question and the electrical-only registration question are both returned as NOT_DETERMINED rather than guessed — the two open conflicts (WA-002 and the 02 ambiguity) are shown beside every answer. S-WA-SEATTLE-PERMIT
11 Permit and verification layer
Washington separates the credential from the permit: the STATE decides who may work (the ch. 18.27 registration and the two trade licences), while the city or county issues the permit. RCW 18.27.110 makes the permit issuer verify the registration before issuing, print the number and give the homeowner-risk notice, and forfeits the permit if the exemption was falsified; ch. 18.106.440 is the plumbing twin. S-WA-18-27-110
A permit is per JOB, a credential is per WHO, and RCW 18.27.130 bars a local contractor licence (with carve-outs for a general business licence and non-registrable contractors) — but the city still sets its permit rules and general business licence. S-WA-19-28-101
Verify the credential that actually applies on the official lookup before relying on any outcome here: L&I Contractor Lookup (covers the ch. 18.27 registration; electrical and plumbing credentials have their own L&I verification paths). S-WA-LNI-VERIFY
Source S-WA-SEATTLE-PERMIT — City of Seattle — Seattle Department of Construction and Inspections (SDCI)
Seattle SDCI — Do You Need a Permit? ($6,000/6-month minor-work threshold, exemptions) — Seattle Do-You-Need-a-Permit / Re-Roof / Electrical / Mechanical pages verbatim (read 2026-10-04)
https://www.seattle.gov/construction-and-inspections/permits/do-you-need-a-permit
Retrieved 2026-10-04 · last verified 2026-10-04
LOCAL EXAMPLE — read 2026-10-04 (HTTP 200). Verbatim: 'Minor repairs or alterations. You don't need a permit for minor repairs or alterations that cost $6,000 or less in any 6-month period. The $6,000 limit is based on fair market value of labor and parts, even if you do the work yourself.' 'You need a permit for any work on load-bearing supports, changes to the building envelope, and work that reduces egress, light, ventilation, or fire resistance no matter how small the project.' Usually no permit: painting/cleaning, re-pointing a chimney, installing kitchen cabinets, paneling/surface finishes over existing systems, insulating existing buildings, hazardous-material abatement, limited in-kind repair; on-grade patios/slabs; sheds <120 sq ft; retaining walls ≤4 ft; fences <8 ft; platforms/walks/driveways <18 in. above grade; dish/panel antennas ≤6.56 ft. 'Even if you don't need a permit, your project must meet all code requirements.' Seattle Residential Code R105.2 / Building Code 106.2 referenced (research §M.1/§N.2).