Frequently Asked Questions

The process runs: initial consultation, site assessment, design and engineering, permit submittal to the City of Brea, plan approval, construction, and final inspection. Most Brea ADUs take 6 to 10 months from first conversation to certificate of occupancy depending on design complexity and city review time. We manage the entire process including all city submittals and revisions. You get a clear timeline in your proposal so you know what to expect at each phase. Call (866) 251-7857 to start your project.

Expect 6 to 10 months total, with the construction phase taking 4 to 6 months once permits are approved. The City of Brea plan review adds 4 to 12 weeks depending on current workload and whether your design needs corrections. Detached new construction takes longer than garage conversions, which can be completed in about 3 to 4 months of construction time. We give you a realistic schedule in writing before you sign anything, so there are no vague promises to regret later.

Yes. We prepare the plans, submit the permit application to the City of Brea, respond to plan check comments, and pull the approved permits. We schedule and pass every required inspection through final sign-off. The homeowner never has to stand at the permit counter or chase a city reviewer. That is the whole point of hiring a design-build ADU company instead of trying to orchestrate separate designers, engineers, and contractors yourself.

Most single-family lots in Brea qualify for at least a junior ADU or a garage conversion under California state law and the city's ADU ordinance. The main requirements are minimum lot size, setback compliance, and available space that does not consume required parking or fire access. Some HOAs in neighborhoods like Olinda Village have aesthetic guidelines but cannot legally prohibit ADUs. We can check your parcel for eligibility in about fifteen minutes during a free site visit. Call (866) 251-7857.

Yes, we build on sloped lots throughout Brea, including the hillside areas around Carbon Canyon and Olinda Ranch. Sloped sites typically require retaining walls, stepped foundations, or pier-and-grade-beam systems, which add engineering cost but are completely routine for us. The key is getting a geotechnical report early so the foundation design matches your actual soil conditions. We include slope considerations in your initial estimate so there are no surprises when engineering comes back.

California state law allows ADUs up to 1,200 square feet for detached units, and Brea follows state standards for most parcels. Attached ADUs can be up to 50% of the primary home's square footage. A junior ADU caps at 500 square feet. Your specific maximum depends on lot size, setbacks, and remaining lot coverage after the primary home is counted. We can max-out your buildable square footage during the design phase so you get every inch the city will approve.

Yes, we handle design, engineering, permitting, and construction under one contract. Our design team creates plans that meet Brea's development standards while maximizing square footage and privacy for both the primary home and the ADU. No separate architect invoices, no finger-pointing between designers and builders. One team, one contract, one fixed price. Call (866) 251-7857 to talk through your vision and see if it fits your lot.

We work with several prefab and panelized systems, including Boxabl and Plant Prefab, which give Brea homeowners faster construction timelines and tighter quality control. Boxabl units arrive as factory-built modules while Plant Prefab offers panelized systems that assemble on site. Each brand fits different site conditions, budgets, and design preferences. We also offer traditional stick-built construction using James Hardie siding and other premium exterior materials. We match the brand to your project rather than forcing one system on every lot.

Sometimes, but not always. Prefab systems like Boxabl and Plant Prefab reduce framing labor and can shorten construction time, which saves on carrying costs and general conditions. However, Brea site preparation, foundation work, utility connections, and permits cost the same regardless of construction method. A prefab ADU in Brea typically lands within the same $180,000 to $320,000 range as stick-built once sitework is included. We price both approaches so you can compare honestly.

We use James Hardie fiber cement siding on many Brea ADU projects because it holds up well to Southern California sun and termite pressure. Stucco remains a popular option that matches most Orange County primary homes. Tuff Shed products are more commonly used for storage structures and office spaces rather than full dwelling units, though we occasionally integrate them as workshop components on larger lots. Your exterior material choice affects both curb appeal and long-term maintenance, and we guide you through the tradeoffs.

Tuff Shed buildings are excellent for storage, workshops, and home offices, but they are generally not suitable as permitted ADUs in Brea when you need a full kitchen, bathroom, and occupancy certification. California ADU code requires specific foundation standards, insulation values, and plumbing systems that standard Tuff Shed structures are not engineered to meet. If you want a permitted dwelling unit with rental income potential, a proper ADU built to code is the right path. We can show you the cost difference between a backyard office and a legal ADU.

Yes. Every pro working under our name is required to hold the license and insurance their state requires, and that includes every trade we bring onto your Brea property. We carry general liability coverage for construction work. You are welcome to request proof of coverage before signing. The point is simple: you should never let an unlicensed crew pour a foundation or run electrical on your property without verifying coverage first. Call (866) 251-7857 and ask us anything about our requirements.

Yes, we pull every permit required by the City of Brea as part of our fixed-price contract. The permit fees are included in your quote, not billed separately after the fact. We also schedule and pass every inspection through final occupancy approval. If a plan check comment comes back requiring revision, we handle the resubmittal at no additional cost to you. You never touch the permit process yourself.

Everyone who works on your project, whether our team or a trade partner, is required to carry the license and insurance their state requires to perform their specific scope of work. We use local Brea and Orange County trades who have done ADU work before, not crews unfamiliar with California residential code. Your project supervisor coordinates every trade on site and verifies that insurance certificates are current before anyone steps foot on your property.

Our phone lines are open Monday through Friday from 7:00 AM to 7:00 PM, and Sunday from 7:00 AM to 7:00 PM. We are closed on Saturdays. When you call (866) 251-7857 during those hours, a live coordinator will answer and connect you with the local Brea project team. If you reach us after hours, leave a message and we will call you back on the next business day or Sunday.

Yes, we regularly step in to complete or correct ADU projects in Brea that stalled or failed inspection. The first step is a site visit to assess what was built, whether it matches the approved plans, and what needs to be corrected to pass a Brea inspection. From there we give you a written fixed-price proposal to finish the work. If a previous contractor left you mid-project, call (866) 251-7857 and we will schedule a free assessment.

ADU construction is planned work, not emergency response, so we do not run a 24/7 repair line. If something goes wrong on a project we built, call us during business hours and we will address it under your workmanship warranty. For urgent structural or utility issues on an occupied ADU, call your utility company or a licensed emergency contractor immediately. Once the immediate issue is stable, call (866) 251-7857 and we will assess what permanent repairs are needed.

Yes, we stand behind our ADU construction with a written workmanship warranty on our labor. The specific terms are spelled out clearly in your contract before construction begins, so you know exactly what is covered, for how long, and how to make a claim if something fails. Manufacturer warranties on components like windows, siding, roofing, and appliances are passed through to you directly. Get everything in writing and never accept a verbal warranty promise from any builder.

Call (866) 251-7857 during business hours and describe the issue. We will schedule an inspection, determine whether the problem falls under our workmanship warranty or a manufacturer warranty, and coordinate the repair either way. Most warranty issues are small things like settling cracks, door adjustments, or caulking failures. If it is our work, we fix it. That is the standard every Brea homeowner should expect, and it is the standard we hold ourselves to.

If you are working with us, you do nothing except let us fix it. We correct the issue, reschedule the inspection, and pass it at no additional cost to you under our fixed-price contract. If a different contractor built your ADU and it is failing inspection, call us for a site assessment. We can identify what the inspector flagged, estimate the correction cost, and either take over the project or give you a clear scope of work to take back to your original contractor. Either way, you will know exactly what is wrong and what it costs to make it right.

Written by the team at Foundry ADU Builders, serving Brea, La Habra, Placentia, Fullerton, Yorba Linda, Anaheim, Buena Park, Villa Park, Orange, Stanton, La Palma, and Garden Grove since 2018.