Room Additions & ADUs contractor serving Anaheim and Orange County CA - Ulloa Construction

CSLB Lic. #1144906. Licensed & Insured.

Room Additions & ADUs in Anaheim
& Orange County

Get a Free Estimate(714) 487-1860

Adding square footage to your Anaheim or Orange County property is one of the best investments you can make. It is also one of the most complex projects to get right without the right contractor. Ulloa Construction manages the full scope of room additions and ADU construction: architectural planning, permit acquisition from your local building department, foundation work, framing, MEP rough-in, drywall, and complete finish work. We design additions that match your existing home's roofline, exterior, and interior flow. Our team holds CSLB License #1144906 and has deep experience with Orange County's seismic requirements and ADU permitting process.

Serving all of Orange County, from Anaheim to San Clemente and everywhere in between.

What's Included in Our Room Additions & ADUs Service

  • Site assessment, design consultation, and architectural planning support
  • Permit acquisition with city building department
  • Foundation design and concrete work (slab, stem wall, or raised)
  • Framing, sheathing, and roofline tie-in to existing structure
  • Electrical, plumbing, and HVAC rough-in and finish
  • Insulation, drywall, texture, and paint
  • Flooring, trim, doors, and windows to match or complement existing
  • ADU kitchen and bathroom construction (full build-out)

How It Works

Simple Steps.
No Surprises.

  1. Step 01

    Free Consultation

    We visit your home, assess the scope, and discuss your vision. No cost and no obligation.

  2. Step 02

    Custom Proposal

    You receive a detailed written estimate covering materials, timeline, and total cost. No hidden fees, no surprises.

  3. Step 03

    Expert Build

    Our licensed OC crew gets to work with daily progress updates and strict quality checkpoints at every stage.

  4. Step 04

    Final Walkthrough

    We walk through every detail with you before considering the job complete. Your satisfaction is the standard.

Start with a Free Consultation

See the Transformation

Drag the slider to compare. Real work by our crew in Orange County.

Before Room Additions & ADUs project in Anaheim CA by Ulloa Construction
After Room Additions & ADUs completed by Ulloa Construction in Orange County CA
AFTER
BEFORE

Why Choose Ulloa Construction

20+ Years Experience

Two decades serving Anaheim and Orange County homeowners with proven craftsmanship.

OC Licensed & Insured #1144906

CSLB License #1144906, full general liability, and workers' compensation on every project.

Seismic Code Specialists

All work meets California seismic requirements. This is critical for Orange County remodels and additions.

Frequently Asked Questions

Common questions from Orange County homeowners about room additions & adus.

How much does a room addition cost in Orange County?
Room additions in Orange County typically cost $200 to $400 per square foot, fully built out. A 300 to 400 square foot master suite addition might run $80,000 to $160,000. A simpler 200 square foot family room addition could come in at $50,000 to $80,000. Costs vary based on foundation type, existing roofline complexity, interior finish level, and required utility upgrades. Ulloa Construction provides free, detailed estimates for all room addition projects in Anaheim and OC.
How long does a room addition take from start to finish?
A room addition project in Anaheim or Orange County typically takes 4 to 9 months from initial design through final inspection. Planning and permit processing takes 1 to 3 months, and construction takes 2 to 6 months depending on scope. We provide a detailed project schedule before starting so you can plan accordingly.
Do you handle all the permits for room additions in Orange County?
Yes. Permits are required for all room additions in Orange County cities, and we handle the entire permitting process. This includes preparing permit applications, submitting plans to the city building department, coordinating any required structural or architectural review, and scheduling all city inspections from foundation through final.
Can a room addition match the existing style of my Anaheim home?
Matching the existing architecture is a core part of how we design and build every room addition. We tie into your existing roofline, match exterior stucco or siding, and replicate interior trim details so the addition feels like it was always part of the original home. We will never leave you with a boxy add-on that looks tacked on.
What is the difference between a room addition and an ADU?
A room addition is attached square footage that becomes part of your primary living area. An ADU (Accessory Dwelling Unit) is a self-contained living unit on the same property as your primary home, with its own entrance, kitchen, and bathroom. ADUs can be detached (like a backyard cottage), attached (an addition with a separate entrance), or converted from existing space like a garage. We build both room additions and ADUs throughout Orange County.
Can you add a room addition in an HOA community in Orange County?
Yes, we regularly work in HOA communities throughout Orange County. HOA-governed properties typically require design review board approval before permitting. We prepare complete HOA submittal packages and manage the approval process on your behalf so you don't have to navigate the HOA process yourself.

Get a Free Room Additions & ADUs Estimate

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CSLB #1144906 · Licensed & Insured · No spam, ever.

Ready to Start Your Room Additions & ADUs?

Call (714) 487-1860 or fill out the form for a free, no-obligation estimate.

Get a Free Estimate(714) 487-1860

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