Fast, Reliable Garage Conversion ADU Across San Pedro
A garage conversion ADU in San Pedro typically runs $95,000-$165,000 all-in, from measured drawings through final inspection, with detached single-car conversions on the lower end and attached two-car projects with full kitchen and bath on the higher end. Most San Pedro garage conversions take 4-7 months from signed contract to occupancy permit, though properties near Point Fermin inside the California Coastal Zone can add 6-10 weeks for the dual-permitting process. Call (424) 344-4822 to schedule your free estimate, and bring any written estimate you already have - we’ll give you a Free Second Opinion on the spot.
We’ve converted garages from the flat interior streets near Gaffey down to the bluff-edge lots along Paseo del Mar. San Pedro’s housing stock - mostly 1920s-1950s Craftsman bungalows and Spanish colonial revival homes on 5,000-7,500 sq ft lots - makes garage conversions the dominant ADU type here. But those older garages hide problems that flat-lot contractors from inland LA rarely anticipate: knob-and-tube wiring, galvanized supply lines, and sub-panels too small to carry a second dwelling unit. Our dispatch and scheduling are coordinated from our Los Angeles office, and our crews serve San Pedro locally every day.
Why Ellery ADU Studio Torrance Is San Pedro’s Preferred Garage Conversion ADU Company
We’ve designed, permitted, and built over 900 ADUs since 2015, the year California’s ADU laws shifted, and a significant share of those have been garage conversions in San Pedro and the surrounding harbor communities. Our Garage Conversion ADU in San Pedro clients receive the same single-contract design-build structure that eliminates the designer-versus-builder blame gap: our architects, permit expediters, and construction crews answer to one written scope at one written price.
San Pedro homeowners find us because they’ve already read the three-star reviews of contractors who quoted low and changed orders high. Our response is documentation, not promises. Every project is governed by The Haven Standard: a written price before work starts (Clause 1), a documented photo record on every visit, and a 365-Day Done Right Promise backed in writing. If the finished ADU is not built to the permitted drawings, we make it right. A live person answers calls 24/7 - no voicemail queue, no callback that doesn’t materialize.
Our license number appears on every page, and our crews are background-checked and uniformed. We don’t subcontract out the permit set or blame the architect when LADBS returns comments. That’s the design-build difference, and it’s why San Pedro homeowners who’ve already been burned once tend to call us second.
Our Garage Conversion ADU Services in San Pedro

Detached Garage Conversion
Detached single-car garages dominate San Pedro’s older neighborhoods, from the bungalows near 25th Street to the post-war tract homes off Western Avenue. A detached garage conversion ADU here typically runs $95,000-$140,000, including the full electrical replacement, plumbing rough-in, and coastal-spec hardware that salt air demands. On bluff-side lots near Point Fermin, we also budget for geotechnical review and engineered foundations - costs that flat-lot conversions in Lakewood or Carson never see. The payoff is a standalone rental unit with its own meter, separate from the main house.

Attached Garage Conversion
Attached garages in San Pedro appear most often on the Spanish colonial revival homes along Palos Verdes Street and the deeper lots off Pacific Avenue. Converting these requires fire separation between the ADU and the primary residence - rated drywall assemblies, possibly a firewall extension - and careful attention to the shared roofline. We typically see attached conversions at $110,000-$155,000. The existing slab is usually adequate, but the shared electrical service almost always needs upgrading, and the coastal air means we spec marine-grade exhaust fans and sealed penetrations at the stucco interface.

Garage JADU
A Junior ADU, or JADU, converts part of an existing garage while the remainder stays as parking or storage. In San Pedro’s 5,000-7,500 sq ft lots, where every square foot matters, a garage JADU lets homeowners keep covered parking for themselves while adding a 500 sq ft max unit with kitchenette and private entrance. These run $75,000-$115,000. The JADU shares the main home’s bathroom (or gets a new one), so plumbing costs drop, but the electrical and structural upgrades remain. We see these most often on the smaller Craftsman lots near Taper Avenue, where a full detached ADU won’t fit the setback.

Carport Conversion
Carport conversions in San Pedro are less common than garage work, but they appear on the mid-century ranches up toward the Palos Verdes border. A carport has no existing slab or walls, so the project becomes closer to new construction - $125,000-$175,000 - with full foundation, framing, and enclosure. The advantage is flexibility: we can design the footprint without working around existing garage door headers or sloped floors. Coastal-spec materials apply here too, especially at the slab edge and any exposed steel columns.

Garage Partition & Bathroom Add
Some San Pedro homeowners want to split a two-car garage into a single-car bay plus a studio or office with bathroom. This partial conversion runs $45,000-$85,000 depending on whether the new space needs a kitchenette. The bathroom add triggers plumbing to the rear of the garage, which on older San Pedro lots may require trenching through concrete to reach the sewer lateral. We map that path during our first site visit and price it in writing - no discovery-phase surprises.

What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
- 2
You get an upfront price rangeHonest numbers before anyone is dispatched.
- 3
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 San Pedro
Our Garage Conversion ADU team specifies and coordinates prefab and modular systems from Abodu, Cover, and Mighty Buildings when the project calls for off-site fabrication, and we source marine-grade anodized window frames from regional suppliers who understand coastal exposure. For stick-built conversions, we use James Hardie fiber-cement siding with sealed joints at all trim interfaces - standard wood trim fails within five years here - and hot-dip galvanized or 304 stainless fasteners throughout. Every material choice is documented in the permit set and the written scope, so there’s no substitution at the truck without your signature.
Common Garage Conversion ADU Problems We See in San Pedro Homes

- Knob-and-tube wiring buried in garage walls. LADBS will not issue an ADU occupancy permit with active knob-and-tube. We find it in roughly half the 1920s-1940s San Pedro garages we open. Full replacement adds $8,000-$15,000, but it’s non-negotiable - and we price it before work starts, not after demo.
- Galvanized steel water supply lines. These clog and corrode, and they’re undersized for a second dwelling unit. We replace with copper or PEX and upsize the meter if needed. On coastal lots, we also spec dielectric unions at every transition to prevent galvanic corrosion from salt air.
- Sub-panels rated for 60 amps. A modern ADU needs 100 amps minimum, often 125. The main panel upgrade ripples back to the service lateral and sometimes the transformer - a cost we identify during our electrical load calculation, not after the drywall is up.
- Standard hardware already rusting from marine layer exposure. On a 1928 Craftsman bungalow off Paseo del Mar near Point Fermin, our crew converted the detached single-car garage, and the pressure-treated sill plate and standard galvanized joist hangers the previous owner had installed two years earlier were already rust-stained and pitted from the salt-laden port air. We replaced the hardware with hot-dip galvanized Simpson Strong-Tie connectors, set the framing on a raised stem wall, swapped the owner’s planned aluminum slider for thermally broken anodized marine-grade frames, and the LADBS inspector signed off the occupancy permit once the sub-panel and knob-and-tube were fully replaced.
Pricing for Garage Conversion ADU in San Pedro, CA
Here’s what garage conversion ADUs cost in San Pedro’s market, with the coastal-spec materials and code compliance built in:
| Project Type | Typical Range |
|---|---|
| Detached single-car conversion | $95,000 - $140,000 |
| Attached two-car conversion | $110,000 - $155,000 |
| Garage JADU (partial conversion) | $75,000 - $115,000 |
| Carport conversion (new foundation) | $125,000 - $175,000 |
| Garage partition + bathroom add | $45,000 - $85,000 |
| Coastal Zone permit add (Point Fermin area) | $4,000 - $8,000 + 6-10 weeks |
| Geotechnical review (bluff-side lots) | $3,500 - $7,500 |
These ranges include drawings, permit expediting, all materials, labor, and final inspection. What moves you within the range: garage size, existing electrical/plumbing condition, coastal zone status, and whether the foundation needs engineering. Under Haven Standard Clause 1, every project is quoted with a written price before any work begins - the words “call for a quote” do not appear on our site because the quote is already in your hand at signing. Call (424) 344-4822 for your exact number; estimates are free.
We Also Serve Cities Near San Pedro

Our crews work daily in Lakewood, Carson, Long Beach, and Torrance. Each city has its own LADBS or local building department quirks, setback rules, and coastal exposure profiles. A garage conversion in Long Beach’s Belmont Shore faces different flood-plain considerations than one in Carson’s flat interior grid. We price and permit for each jurisdiction specifically - no cookie-cutter scopes.
Serving San Pedro, CA - Our Local Coverage Area
We’re based in the San Pedro 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 - Garage Conversion ADU in San Pedro

Only if your property sits within the California Coastal Zone, which covers the bluff-side streets near Point Fermin and portions of the waterfront. Most interior San Pedro lots west of Gaffey and north of 25th Street fall outside the zone and need only LADBS approval. If you’re coastal zone, the dual-permitting adds 6-10 weeks and $4,000-$8,000. Call (424) 344-4822 and we’ll check your parcel map in the first five minutes of the call - no charge.
LADBS routinely flags foundation permits on bluff-edge lots near Point Fermin for geotechnical review because the coastal bluff soils have documented instability. It’s not a random hold - it’s a standard trigger for that topography. Flat-lot conversions in San Pedro’s interior or in neighboring Carson rarely hit this. If your lot is on or near the bluff, we budget the soil report and engineered retaining wall into our written price from day one, so the 6-10 week review doesn’t become a surprise stall.
We spec hot-dip galvanized or 304/316 stainless Simpson Strong-Tie connectors, hot-dip galvanized anchor bolts, and stainless or ceramic-coated roofing fasteners. Standard electro-galvanized or zinc-plated hardware corrodes within a few years in San Pedro’s marine layer blowing off the Port of Los Angeles. The price gap between coastal-spec and inland-spec hardware runs roughly 15-25% on the framing package, but the cheap spec costs more within a decade when you’re replacing rotted sill plates and failed hangers. We document every fastener grade in the permit set.
No. LADBS will not issue an ADU occupancy permit with active knob-and-tube wiring, and roughly half the 1920s-1940s San Pedro garages we open still have it buried in the walls. The sub-panel also needs upgrading to 100 amps minimum. We price the full electrical replacement into every written quote for pre-1950 San Pedro garages - no exceptions, no surprises at rough inspection. Call (424) 344-4822 and we’ll walk through what we found on your specific block.
Yes, though they’re less common than garage conversions here. A carport conversion requires full foundation, framing, and enclosure - closer to new construction than a garage retrofit - and typically runs $125,000-$175,000. We see them most on the mid-century ranches toward the Palos Verdes border. The same coastal-spec materials apply: marine-grade fasteners, sealed Hardie trim joints, and thermally broken window frames. Call (424) 344-4822 to schedule a free estimate and we’ll assess the existing slab and roof structure on the first visit.
Written by Nadia Ellery, Owner at Ellery ADU Studio, serving San Pedro since 2015.