Fast, Reliable Garage Conversion ADU Across Pasadena
A garage conversion ADU in Pasadena typically runs $95,000-$165,000 all-in, from measured drawings through final inspection, depending on whether the structure is attached, detached, or requires a full electrical service upgrade. We’re Ellery ADU Studio, and our Garage Conversion ADU team coordinates design, permitting, and construction under one written contract at one written price. Dispatch and scheduling run from our Los Angeles office, but our crews serve Pasadena locally and understand the dual-track permitting reality here: city building department plus Pasadena Water and Power’s entirely separate electrical queue. Call (626) 427-9813 to schedule your free estimate.
Why Ellery ADU Studio Pasadena Is Pasadena’s Preferred Garage Conversion ADU Company
We’ve designed, permitted, and built over 900 ADUs since 2015, the year California’s ADU laws shifted statewide. Every one carried a written price before work started, per Haven Standard Clause 1. Our Pasadena clients receive the same documentation: a permit set treated as the core product, not an afterthought; a documented photo record on every visit; and the 365-Day Done Right Promise, backed in writing before the project begins.
Pasadena’s garage stock is unlike coastal LA. The 1910s-1940s Craftsman bungalows and Spanish Colonial Revival homes that dominate neighborhoods from Bungalow Heaven to the Linda Vista hillside were built with detached alley garages, knob-and-tube wiring, and 100A electrical service that modern ADU codes simply do not allow. A contractor who treats Pasadena like West LA misses the PWP coordination and loses a month.
Our license number appears on every page, verified. Our crews are background-checked and uniformed. And a live person answers calls 24/7 - no voicemail queue, no callback promise that evaporates.
Our Garage Conversion ADU Services in Pasadena
Detached Garage Conversion
This is the most common project we see in Pasadena. The city’s older grid neighborhoods - Bungalow Heaven, Washington Square, the alley-served blocks north of Colorado Boulevard - are full of detached garages built between 1920 and 1940 with 4-inch slabs, uninsulated walls, and electrical service that was never meant to power a dwelling unit. We start with a full structural and MEP assessment, coordinate the PWP service upgrade in parallel with city permit submission, and price every finding in writing before demo. A typical detached garage conversion in Pasadena runs $110,000-$165,000 all-in.
Attached Garage Conversion
Attached garages in Pasadena’s postwar ranch pockets and hillside midcentury tracts present different constraints: fire separation between the ADU and primary residence, shared-wall sound transmission, and often a direct tie-in to the main home’s HVAC that the permit set must address explicitly. We model the energy code compliance as part of the initial drawings, not as a change order after framing opens. Attached conversions in Pasadena typically run $95,000-$140,000.
Garage JADU
A Junior ADU carved from an existing garage must share bathroom facilities with the primary residence and meet owner-occupancy requirements under state law. In Pasadena, we see these work best on smaller alley garages in the Historic Highlands or on converted portions of two-car structures where the remaining bay stays in service. The JADU path saves on kitchen and bathroom infrastructure but still triggers PWP review if any electrical load is added. Typical range: $75,000-$115,000.
Carport Conversion & Garage Partition with Bathroom Add
Carport conversions require full enclosure, slab work or foundation piers, and often a complete roof rebuild - essentially a new structure wearing an old footprint. In Pasadena’s hillside fire zones, this also means ember-resistant venting and ignition-resistant exterior materials. Garage partitions, where we split a two-car structure into a one-car garage plus ADU with its own bathroom, demand careful plumbing routing on alley-served lots where sewer lateral depth is already marginal. These run $85,000-$130,000 depending on utility extension length.
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.
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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 Coordinate in Pasadena
Ellery ADU Studio specifies and coordinates prefab and modular systems from Abodu, Cover, and Dvele within the same single-contract framework that governs our stick-built conversions. For Pasadena clients considering a hybrid approach - a factory-built unit on a garage-demolition footprint - we handle the site prep, utility rough-in, and final connection as part of the same written scope. No designer-builder blame gap. The permit set, the module delivery, and the local finish work are all under Haven Standard Clause 1 pricing.
Common Garage Conversion ADU Problems We See in Pasadena Homes
- Knob-and-tube wiring behind intact drywall. We open a 1920s garage in the Bungalow Heaven HPOZ and find cloth-insulated conductors still live. The PWP service upgrade becomes non-negotiable, and we price the full rewire before the permit set is finalized.
- Rotted sill plates from alley drainage. Pasadena’s alley-served garages sit below grade on the alley side. Years of runoff wick into the mudsill. We sister the damaged framing and specify pressure-treated replacements, but only after documenting the extent in writing.
- Undersized HVAC specified for coastal LA. Pasadena’s inland valley location means design temperatures of 95-100°F, not 85°F. A mini-split sized for Santa Monica fails here. We spec heat-load calculations using Pasadena-specific climate data.
- PWP meter-socket coordination missed. Contractors who pull city permits first and call PWP second routinely face a four-to-six-week delay on final sign-off. We file both tracks simultaneously from day one.
Pricing for Garage Conversion ADU in Pasadena, CA
| Project Type | Typical All-In Range |
|---|---|
| Attached Garage Conversion | $95,000 - $140,000 |
| Detached Garage Conversion | $110,000 - $165,000 |
| Garage JADU | $75,000 - $115,000 |
| Carport Conversion | $85,000 - $130,000 |
| Garage Partition + Bathroom Add | $85,000 - $130,000 |
These ranges include measured drawings, the full permit set, all city and PWP fees, construction, and final inspection sign-off. What moves the number: electrical service upgrade necessity, foundation repair extent, fire-zone material requirements, and HPOZ design-review rounds. Under Haven Standard Clause 5 (No Surprises), the scope is locked at signing. Any condition we discover during structured pre-demo inspection is priced and approved in writing before we proceed - not invoiced as a surprise.
We also offer a Free Second Opinion on any written estimate already in hand. Call (626) 427-9813 for your written quote.
We Also Serve Cities Near Pasadena
Our crews work throughout the San Gabriel Valley, including Garage Conversion ADU in Pasadena and neighboring Alhambra, Temple City, Rosemead, and Monterey Park. Each city carries its own utility jurisdiction and permitting rhythm; we adjust the permit strategy accordingly rather than apply a Pasadena template elsewhere.
Serving Pasadena, CA - Our Local Coverage Area
We’re based in the Pasadena 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 Pasadena
Yes. Pasadena Water and Power controls all electrical service upgrades independently of the city’s building department, so your project needs two parallel tracks: city plan check and PWP meter-socket coordination. We file both simultaneously. Call (626) 427-9813 to discuss your specific service size and timeline.
Knob-and-tube wiring, 100A panels with no spare capacity, rotted sill plates from alley drainage, and slabs without modern moisture barriers. In Bungalow Heaven, we converted a 1920s detached alley garage and found cloth-insulated knob-and-tube plus a sill plate rotted from years of the alley-side grade. We coordinated the PWP meter-socket upgrade before demo, swapped the panel to 200A, sistered the damaged framing, and priced every finding in writing before we started - so the client approved the delta and PWP’s own inspection never stalled the build.
Yes, if your property sits within a Historic Preservation Overlay Zone such as Bungalow Heaven, Prospect Park, or the Civic Center. Pasadena layers HPOZ design review on top of state-mandated ADU streamlining, requiring the ADU to match the architectural character of the host property. We address this in the initial drawings, not as a late-stage revision. Call (626) 427-9813 to confirm your property’s zone status.
Yes, provided the resulting unit meets Junior ADU requirements: 500 square feet maximum, bathroom may be shared with the primary residence, and the owner must occupy either the main home or the JADU. In Pasadena’s alley-served neighborhoods, we see this work well on smaller detached structures where a full ADU kitchen would consume too much of the limited footprint. The JADU still triggers PWP review for any added electrical load.
A correctly sized mini-split heat pump or equivalent system, specified using Pasadena’s 95-100°F design temperatures rather than coastal LA assumptions. The inland valley heat means systems adequate in West LA are routinely undersized here. We run Manual J load calculations as part of the permit set, and we specify equipment with enough capacity for Pasadena’s actual climate, not a milder one.
Written by Nadia Ellery, Owner at Ellery ADU Studio, serving Pasadena since 2015.