Fast, Reliable New Detached ADU Across Long Beach
A new detached ADU in Long Beach typically runs $220,000-$420,000 all-in, from the first site survey through final inspection, depending on whether you build custom or specify a prefab or modular system. We’re Ellery ADU Studio, and our New Detached ADU in Long Beach work is coordinated from our Los Angeles office with crews serving Long Beach neighborhoods directly. Call (562) 263-3350 to schedule your free estimate - every project receives a written price before any work starts, per Haven Standard Clause 1.
Why Ellery ADU Studio Huntington Beach Is Long Beach’s Preferred New Detached ADU Company
We’ve designed, permitted, and built ADUs in Long Beach since 2015, the year California’s ADU laws shifted. That’s 900+ ADUs across the state, with a documented photo record on every visit and a 365-Day Done Right Promise backed in writing.
Long Beach is a charter city with its own independent building department - not LA County’s, not LA City’s. That means plan check, fee schedules, and inspection sequences follow Long Beach’s staff and process alone. We’ve navigated it hundreds of times. Our crews know the difference between a Rose Park alley-grid parcel and a 1950s East Long Beach ranch slab near Lakewood, and we price for what we find, not what we guess.
Our license number appears on every page, verified. Background-checked, uniformed crews. A live person answers calls 24/7 - no voicemail queue. And we offer a Free Second Opinion on any written estimate already in your hand.
Our New Detached ADU Services in Long Beach
Custom Built ADU
Custom built ADUs in Long Beach typically run $280,000-$420,000 all-in. This is the right path when your lot has constraints - a tight setback on a Belmont Shore parcel, a blufftop grade change in Bluff Park, or you want the unit to match your 1920s Craftsman detail-for-detail. We handle the full permit set, the structural design for Long Beach’s seismic requirements, and the build under one contract at one written price. No designer-versus-builder blame gap.
Prefab ADU Installation
Prefab ADU installation in Long Beach typically runs $220,000-$340,000, including site prep, foundation, utility tie-ins, and Long Beach permit fees. We specify and coordinate systems from Mighty Buildings, Plant Prefab, and Tuff Shed - whichever unit fits your lot and budget. The factory build shortens on-site time, which matters on narrow Long Beach lots where staging space is tight. We manage the crane schedule, the utility trench, and the final inspection sequence with Long Beach’s building department.
Modular ADU
Modular ADUs in Long Beach typically run $240,000-$360,000. These are code-compliant, volumetric units delivered in sections and set on a permanent foundation. We work with Boxabl and other modular brands to match Long Beach’s zoning - including the alley-access configurations that Rose Park and Wrigley parcels accommodate uniquely well. The permit set includes the manufacturer’s engineering sealed for California, plus our site-specific foundation and utility plans.
Studio ADU & 1-Bed & 2-Bed ADU
Studio ADUs in Long Beach typically run $220,000-$300,000; 1-bedroom units $260,000-$360,000; 2-bedroom units $320,000-$420,000. Size drives cost, but so does utility capacity - older Long Beach mains in the bungalow districts often need upsizing for a 2-bedroom unit, and we identify that in the initial site survey, not after walls are open. Every bedroom adds a window egress requirement, a closet depth, and a heating load that we calculate for Long Beach’s mild marine climate.
What happens when you call
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A real person answersNo phone trees - you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Long Beach
We specify and coordinate prefab and modular systems from Mighty Buildings, Plant Prefab, Tuff Shed, and other manufacturers - all within the same single contract. For Long Beach customers, this means we stock local parts for common service items, coordinate factory delivery to minimize on-site staging, and manage the brand’s warranty documentation alongside our own 365-Day Done Right Promise. Turnaround on prefab units typically runs 4-6 months from permit approval to final inspection, faster than custom builds in most cases.
Common New Detached ADU Problems We See in Long Beach Homes
- Knob-and-tube wiring behind original stucco. On a 1928 Craftsman bungalow in Rose Park with a detached single-car garage off the alley, our crew opened the walls and found cloth-wrapped knob-and-tube wiring, a rotted sill plate behind salt- and termite-damaged stucco, and a slab that had never been waterproofed - so we stopped, wrote a priced change order, and got written approval before proceeding. The framing was sistered and reinforced, the electrical panel replaced, and the garage came back as a permitted detached ADU with its own alley address and fully independent utilities, converting what would have been a blind remodel surprise into a signed line item.
- Salt-air corrosion in coastal zones. Properties in Belmont Shore, Naples Island, and the Bluff Park blufftop corridor face persistent salt-air exposure that corrodes framing hardware, electrical panel lugs, and plumbing fittings inside older detached garages. These failures aren’t visible until demo opens the walls, and they force emergency re-inspection with Long Beach’s own building staff if discovered mid-project. We inspect for this during our initial site survey and write allowances into the contract.
- Earthquake-era framing and undersized members. Many Long Beach bungalows were reconstructed or reinforced after the 1933 Long Beach earthquake, but the work didn’t always extend to detached garages. We regularly find 2×4 rafters at 24 inches on center, no shear panels, and sill plates bolted with pre-code anchors that don’t meet current standards. Upgrading this is line-itemed in the original quote, not sprung later.
- Fire-separation failures on attached garages. Converting an attached 1950s-1960s East Long Beach ranch garage near Lakewood without planning fire-separation upgrades triggers a plan-check rejection or a failed inspection because the separation detail - rated drywall, draft-stopping, possibly a fire-rated door - was never in the drawings. We catch this in the permit set phase, not at inspection.
Pricing for New Detached ADU in Long Beach, CA
| ADU Type | Typical Range (Long Beach) | What’s Included |
|---|---|---|
| Studio ADU (custom) | $220,000-$300,000 | Design, permit set, build, final inspection |
| 1-Bedroom ADU (custom) | $260,000-$360,000 | Design, permit set, build, final inspection |
| 2-Bedroom ADU (custom) | $320,000-$420,000 | Design, permit set, build, final inspection |
| Prefab ADU installation | $220,000-$340,000 | Site prep, foundation, unit, utility tie-ins, permit fees |
| Modular ADU | $240,000-$360,000 | Foundation, module delivery, set, finish, utilities, inspection |
What moves the number: foundation condition, utility distance from main, soil compaction, and whether the existing structure is salvageable or comes down entirely. Long Beach’s charter-city permit fees run separately from LA County’s and are itemized in every quote. Under Haven Standard Clause 1, the written price comes before any work starts. Under Clause 5 (No Surprises), the scope locks at signing; no door-side upsells, no scope creep. If we find something unexpected, we stop, photograph it, price it, and get your written approval. Call (562) 263-3350 for your free estimate.
We Also Serve Cities Near Long Beach
Our New Detached ADU crews work throughout Seal Beach, Lakewood, Los Alamitos, and Cypress - each with its own permitting path, each with housing stock distinct from Long Beach’s. Lakewood, for instance, runs through LA County building, not a charter city, so the plan-check timeline and fee schedule differ meaningfully. We know which jurisdiction governs your parcel and price accordingly.
Serving Long Beach, CA - Our Local Coverage Area
We’re based in the Long Beach area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs - New Detached ADU in Long Beach
Long Beach is a charter city with its own independent building department, separate from both the City of Los Angeles and LA County. That means ADU plan check, permitting fees, and inspections run entirely through Long Beach’s own staff and follow its own process timeline. Lakewood uses LA County; Los Angeles uses LA City. The forms, the fee calculators, and the inspection sequences are not interchangeable. We file in the correct jurisdiction based on your parcel’s address. Call (562) 263-3350 for an exact quote - estimates are free.
Yes. A large share of parcels in Rose Park and Wrigley sit on Long Beach’s historic alley grid, and the city’s building department accommodates alley-facing ADUs with independent postal addresses, utility meters, and pedestrian access. This is a configuration Long Beach’s ADU pathway specifically allows, and one that most neighboring cities cannot replicate at this scale. The separate address typically commands higher rents because tenants never share an entrance with the primary dwelling. We document this pathway in the permit set from day one. Call (562) 263-3350 to check your parcel’s alley access.
Cloth-wrapped knob-and-tube wiring, rotted sill plates behind salt-damaged stucco, unwaterproofed slabs, and earthquake-era framing that doesn’t meet current standards. These are not edge cases in Long Beach’s 1920s-1950s bungalow stock. We inspect for visible indicators during our initial site survey and write allowances into the contract. If we find something worse, we stop, photograph it, write a priced change order, and get your written approval before proceeding. No blind surprises. Call (562) 263-3350 to schedule your free estimate.
Yes. Persistent salt-air exposure in these zones corrodes framing hardware, electrical panel lugs, and plumbing fittings inside older detached garages, often invisibly until demo opens the walls. We’ve replaced panels where the bus bars were pitted through, and re-piped galvanized lines that looked sound outside but were paper-thin inside. We inspect for corrosion indicators during site survey and write remediation allowances into the contract. If the damage exceeds the allowance, we stop and get written approval on a priced change order. Call (562) 263-3350 for an exact quote - estimates are free.
These homes - common east of Lakewood Boulevard, abutting Lakewood proper - typically have slab foundations, attached garages, and post-WWII framing that triggers fire-separation requirements: rated drywall between dwelling and garage, draft-stopping at the plate line, sometimes a fire-rated door. The conversion approach is structurally different from a detached bungalow garage in Rose Park. We design the separation detail into the permit set from the start; without it, Long Beach plan check rejects the drawings or the inspector fails the job. Call (562) 263-3350 to review your garage type and get a written quote.
Ready to price a new detached ADU on your Long Beach property? Call (562) 263-3350 to schedule your free estimate. You’ll receive a written price before any work starts, a documented photo record on every visit, and the full protection of The Haven Standard - including our 365-Day Done Right Promise, backed in writing.
Written by Nadia Ellery, Owner at Ellery ADU Studio, serving Long Beach since 2015.