ADU Contractors in Rancho Cucamonga, CA — License-Verified Contractors
Every contractor below holds an active California license with an office of record in Rancho Cucamonga, 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
582 license-verified contractors based in Rancho Cucamonga — page 5 of 12
H 2 M Construction Inc
ABH E Hoist Equipment
C-36H K Construction Inc
BC-8H L Hitchcock Construction Inc
ABC-8Hall George Electric
C-10Hamud Mark Anthony
BHandy Solt
BHandysolt Inc
BHanna Rifky B
ABHao Fan Company
BHarrington Construction Co Inc
Harrington West Construction Co Inc
BHaven Electric
Haven Automation And Controls Inc
C-10Haynes Douglas General Contractor
BHayward Environmental Consulting H E C
AHAZHaz Mat Trans Inc
AHAZHensley Electric Inc
C-10Heritage Custom Landscapes Inc
BC-10C-27D-28D-49D-63High Integrity Construction
BD-24Highball Signal Inc
AC-10Hillty Electric
C-10Hofmann C A Construction Inc
BC-9Hoist Pro
C-36D-21Holguin & Holguin Enterprises Inc
ABC-21Home Master International
All About Cabinets Inc
BHome Repipe Plumbing LLC
C-36Home Spruce Corporation
BHowell Richard
BHuber Construction
BHurtado Construction
BC-27Hutchison Ryan
BHyun Suk Ho
BIbrahim Andrew Mark
BInertia Design Company
BInline Electric Inc
C-10Insta Painting & Construction
Insta P & C Inc
BC-33Installation Pro Plumbing LLC
C-36D-34Intelligent Engineered Systems And Services
AHAZIntelligent Fire Solutions
G N A Fire Electric Inc
C-10C-16Interior Environmental Specialists
Oshi Construction Inc
BInvert Construction Corp
AASBBC-10C-21C-42HAZIrontek Inc
BC-23Iverson Construction
BIverson David R Construction Inc
BJ & K Welding
Kathleen Brugger
AC-60J B M Remodeling LLC
BJ D Electric
C-10J D K Construction & Consulting Services Inc
BJ M H Construction
BJ M S Construction
BData source: CSLB public records as of November 6, 2026 · Verify any license at CSLB