ADU Contractors in El Cajon, CA — License-Verified Contractors
Every contractor below holds an active California license with an office of record in El Cajon, verified against CSLB public data as of November 6, 2026: general builders — A (General Engineering) and B (General Building), the classifications that can build an ADU — and the licensed trades ADU construction uses, C-10 Electrical, C-36 Plumbing and C-5 Framing & Rough Carpentry. Listings are alphabetical; the featured builder is labeled, never ranked.
ADU rules — setbacks, size limits, parking, and fees — are set by the local jurisdiction and change often. Before you hire, read the ADU permit process guide and the Southern California ADU cost guide, and verify any license free at CSLB.
Mars Construction Industries Corp
ADU Cities' own design-build team
CSLB #1138550 · A · B · C-36 · C-20
Building ADUs across Los Angeles, Orange, Riverside, San Bernardino, San Diego & Ventura counties
821 license-verified contractors based in El Cajon — page 17 of 17
West Coast Air Conditioning Company Inc
AASBBC-10C-20C-36C-4C-43C-51West Coast Drywall
W C D Inc
ABC-9West Coast General Corporation
ABWest Coast General Group A Joint Venture
ABWest Coast General Group Inc
ABWest Coast Heating Air Solar Plumbing
West Coast Appliance Services Inc
C-10C-20C-36Western Plumbing And Piping Inc
C-36Whitacre D A Construction Inc
BC-51Whitaker Construction Corporation
BWhitaker Russell James
BWidick Robert Plastering
BC-35Wiesner C J Construction Inc
BWilliard Homes LLC
BWoodworks Unlimited
BWorley Steven Construction Inc
ABWright Brothers Plumbing Inc
C-36Wright Custom Building Inc
BXcel Remodeling Inc
BZack Paradise
C-10Zee Construction & Renovations Inc
BData source: CSLB public records as of November 6, 2026 · Verify any license at CSLB