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 11 of 12
Sterling Synergy Systems Inc
C-10C-7Stiles Construction Services Inc
BStone Camarin
C-20C-36Strike Electrical Solutions
C-10Strong Hold Construction Inc
BSui Wen
BSuperior Electrical Mechanical & Plumbing Inc
BC-10C-20C-36C-38Superior Tank Co Inc
ASuperior Tank Solutions Inc
AC-33Szanco Inc
BT C B Construction Inc
BT S R Construction And Inspections
ABT T S I Network Communications
T T S I Electric Inc
C-10C-7Tang Qian
BC-10Terra Nostra Builders Inc
BThien Fui Ming Construction
BThomas Custom Framing
C-5Tiburon Telecommunications Inc
C-10C-7Tj's General Engineering Inc
AC-12Tjb Construction LLC
BTobin Construction Inc
ABTodd Anthony Construction Services
Todd Anthony Brazeau Inc
BC-39Toyto Construction Inc
BTres Facility Services Inc
BTriple Q Construction Inc
BTrl Systems Incorporated
C-10C-16Trust General Contracting
BTryon Electric
C-10Ts Epoxy Flooring
Ts Construction Group Inc
BD-12U S A Plumbing Service Incorporated
C-36Ucorr Innovative Solutions Inc
AC-10Underground Specialists Inc
AUnited Builders
Andronicos Henry Inc DBA United Builders
BC-17United Construction Company
A & J's Construction Company Inc
BC-29United Coverings Inc
BC-15C-54United One Engineering
ABC-10United Plumbing
United Plumbing & Restoration
BC-36United Security Systems Inc
C-10Universal Construction & Design
BUpland Fire Protection A Inc
C-10C-16Uptown Interiors Inc
BUtility Plumbing Services Inc
C-36V K Plumbing
C-36V L C Z Interior Inc
BV M Home Improvement
BVan Lund Construction
BVan Lund Roofing And Solar
Lund Van Construction Inc
BC-39C-46Veith Electric
C-10Versatile Construction
BData source: CSLB public records as of November 6, 2026 · Verify any license at CSLB