Home Additions & ADU in Universal City - One Fixed Price, Permits Handled

Fast, Reliable Home Additions & ADU Across Universal City

Home additions and ADU construction in Universal City typically run $45,000-$130,000 for a room addition and $90,000-$220,000 for a detached ADU, depending on hillside conditions, fire-code requirements, and whether you’re building against the mountain or on a flat pad. Universal City is unincorporated LA County territory, which means your permits go through LA County Building & Safety in Altadena, not LADBS, and the plan-check queue, the inspectors, and the code interpretations are all different from a job one block away inside the Los Angeles city limits. That distinction catches out-of-area contractors constantly, and it changes how we schedule, how we design, and how we price. Call (877) 610-1318 for a free estimate from a team that already knows the drill.

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Key Takeaways:

• Home additions in Universal City run $45,000-$130,000; detached ADUs run $90,000-$220,000.
• Universal City’s unincorporated status means LA County permits, different inspectors, and VHFHSZ fire-code compliance on nearly every hillside job.
• Steep cut-and-fill lots in the Santa Monica Mountains foothills make retaining walls, slope drainage, and hillside foundations routine scope items here.
• Barrett & Sons Construction is owner-operated, founded 1998, with Tom Barrett’s name and license number published and verifiable.

Why Barrett & Sons Construction Is Universal City’s Preferred Home Additions & ADU Company

Tom Barrett founded this company in 1998 and his sons run the crews. When you call about a home addition in Universal City, you’re not getting a dispatcher in another state. You’re getting a live person, often Tom himself, who knows what a Cahuenga Pass hillside lot does to a foundation bid. Our customers in the 91608 ZIP code deal with a set of conditions that don’t exist in Studio City or North Hollywood: unincorporated LA County jurisdiction, Very High Fire Hazard Severity Zone building standards under California Building Code Chapter 7A, and hillside sites where the retaining wall is the first thing on the plan, not an afterthought. We’ve built additions and ADUs on those slopes, and we know what the county plan-check staff in Altadena will flag before they flag it.

Every job we take in Universal City comes with a written scope, written allowances, and written change orders before any scope change touches the job. The permit inspector works for you, not for me, and we treat every inspection like it’s the one that matters. If something isn’t done right, the 90-Day Done Right Promise is written on the contract, and one call brings Tom back. No fine print, no runaround.

Our Home Additions & ADU Services in Universal City

ADU Design & Permitting

A detached ADU on a Universal City hillside lot starts with a conversation about slope, setback, and fire zone. The Cahuenga Pass sits inside a CAL FIRE Very High Fire Hazard Severity Zone, so your ADU plans need ember-resistant vents, ignition-resistant exterior assemblies, and Universal City Roofing with Class A assembly before LA County will even look at the foundation detail. We handle the design and the permit package together, because in 91608 the two can’t be separated. Expect the permit path to run through LA County’s Altadena plan-check queue, not LADBS, and expect us to have the Chapter 7A compliance already baked into the drawings.

Garage Conversion ADU

Garage conversions in Universal City carry a different cost profile than attached additions, and the parking replacement requirement is the first thing the county checks. Most 91608 garages sit on the downhill side of the lot, which means drainage and retaining responsibility follow the conversion. Our Home Additions & ADU team has converted garages on hillside lots where the floor slab needed structural tying into a slope retention system, and we’ll tell you in the estimate whether your garage is a simple conversion or a structural project wearing a conversion’s clothes.

New Detached ADU

Building a new detached ADU in Universal City means designing for the mountain, not against it. Cut-and-fill lots from the mid-century to 1980s dominate the residential pockets of 91608, and a new foundation on fill soil needs geotechnical review before the first form goes up. We pull permits, we schedule the inspections, and we write every allowance down before it becomes a surprise. The cost range for a new detached ADU here runs $90,000-$220,000, and the spread comes down to slope work, utility trenching, and how much of the hillside has to be re-engineered to hold the structure.

Junior ADU & Interior Conversion

A Junior ADU inside an existing Universal City home is usually the most cost-efficient path to rental income or family housing, because it avoids new foundation work entirely. Interior conversions of a bedroom, den, or garage-adjacent space still require county permits, and in a 91608 apartment complex or hillside home, the scope often includes fire-rated separation, sound attenuation, and a separate entrance that works with the slope. We walk the site with you, measure what’s there, and give you a written line-item quote before anything moves forward. This is also where our Bathroom Remodeling in Universal City crew often steps in, since a Junior ADU usually needs a kitchenette or full bath added to the converted space.

Trusted Brands We Service in Universal City

We carry Simonton, Ply Gem, and PGT Windows & Doors in Universal City on our home addition projects, because hillside homes need glazing that handles sun exposure, wind, and the occasional ember event during fire season. PGT impact-rated windows are a staple on our 91608 additions where the county’s Chapter 7A requirements push for ignition-resistant assemblies. We order direct from the manufacturers and stage materials locally so your Universal City project isn’t waiting on a shipping delay. You can look up every brand we install.

Common Home Additions & ADU Problems We See in Universal City Homes

• Hillside foundation issues on cut-and-fill lots. Many 91608 homes were built in the 1960s through 1980s on compacted fill, and adding square footage means the new foundation has to tie into soil that’s been settling for decades. We bring in geotechnical review early, not after the excavation opens up a surprise.
• County permit confusion for unincorporated territory. Universal City residents routinely tell us a previous contractor assumed the job went through LADBS because the address says “Los Angeles” on the mail. It doesn’t. LA County Building & Safety in Altadena handles the plan check, and the forms, inspectors, and code staff are entirely different. Our team already knows which queue your addition sits in.
• Chapter 7A fire-code retrofitting on existing structures. Any addition or ADU that touches the exterior in a VHFHSZ classification triggers ignition-resistant requirements: ember-resistant vents, specific exterior cladding, Class A roofing. Flatland contractors miss these line items and the change order shows up mid-job. We write them into the first estimate.
• Slope drainage and retaining wall failures. The Santa Monica Mountains foothills around the Cahuenga Pass shed water fast during winter storms, and an addition that changes the grade can redirect runoff into a neighbor’s foundation or your own garage. Retaining walls and drainage systems are routine scope items on Universal City additions, not optional upgrades.

Pricing for Home Additions & ADU in Universal City, CA

We Also Serve Cities Near Universal City

Barrett & Sons Construction serves Home Additions & ADU in Universal City along with the surrounding communities of Studio City, North Hollywood, Hollywood, and West Hollywood. If you’re in a neighboring ZIP and need an addition or ADU, call us and we’ll confirm coverage. We also handle Kitchen Remodeling in Universal City for homeowners who want the addition and the adjacent kitchen done as one coordinated project.

FAQs - Home Additions & ADU in Universal City