Garage Conversion ADU in Pasadena - Design, Permits and Build Under One Contract

Fast, Reliable Garage Conversion ADU Across Pasadena

A garage conversion ADU in Pasadena typically runs $95,000-$165,000 all-in, drawings through final inspection, with most detached single-car alley garages falling in the $110,000-$140,000 range. We’re Nadia Ellery’s Garage Conversion ADU team at Ellery ADU Studio, and we coordinate dispatch and scheduling from our Los Angeles office with crews serving Pasadena locally. If you’re looking at a 1920s Craftsman with a detached garage off a rear alley in Bungalow Heaven, or a Spanish Colonial Revival with an attached carport near the Arroyo Seco, the conditions we find inside your walls will shape your final price more than any square-foot estimate.

Call (747) 322-4648

Call (747) 322-4648 to schedule your free estimate. We bring a written price, not a callback promise.

Why Ellery ADU Studio Burbank Is Pasadena’s Preferred Garage Conversion ADU Company

Pasadena’s housing stock doesn’t forgive guesswork. The majority of garages we convert here were built between 1910 and 1940, and they carry the electrical, foundation, and structural conditions of that era. Our crews have documented photo records from over 900 ADUs designed, permitted, and built since 2015, and a significant share of those passed through Pasadena’s Planning and Community Development Department - including Historic Preservation Commission review for contributing properties in Bungalow Heaven and other landmark districts.

Pasadena clients receive the same single-contract design-build model we deliver across Los Angeles County: drawings, permit set, and construction under one written price, with no designer-versus-builder blame gap. Under Haven Standard Clause 1, that price is fixed before any work starts. Our license number appears on every page, and our background-checked, uniformed crews work with the specific materials and methods Pasadena’s historic overlays and fire hazard zones require.

A live person answers calls 24/7. If you already have a written estimate in hand, we offer a Free Second Opinion.

Our Garage Conversion ADU Services in Pasadena

Detached Garage Conversion

This is Pasadena’s most common ADU type. The city’s 1910s-1940s Craftsman bungalows typically have detached single-car garages accessed off rear alleys - narrow, concrete-slab structures with raised post-and-pier foundations that have settled over a century of foothill freeze-thaw cycles. We open these walls first, document what we find, and price any knob-and-tube rewire, panel upgrade, or sill repair as a signed change order before framing begins. For contributing properties in Bungalow Heaven or other historic districts, we specify wood windows and pitched rooflines from the start so Historic Preservation Commission review doesn’t force a redesign.

Attached Garage Conversion

Attached garages in Pasadena’s Spanish Colonial Revival and mid-century homes share a wall with the main house, which changes the fire-separation and sound-attenuation requirements in your permit set. We design the firewall assembly, the utility separation, and the independent meter configuration as part of our drawings - not as an afterthought. In north Pasadena addresses near the San Gabriel Mountains, we also verify VHFHSZ status early; if your property falls in a Very High Fire Hazard Severity Zone, ember-resistant venting and ignition-resistant cladding become code requirements, not upgrades.

Garage JADU

A Junior ADU conversion keeps the garage footprint under 500 square feet and requires owner occupancy in either the main house or the JADU - a structure that works well for Pasadena homeowners who want rental income without the full ADU permit path. We evaluate whether your alley garage meets JADU utility-sharing rules and whether Pasadena’s historic overlay imposes additional design constraints. The JADU route can save months on permitting, but only if the initial survey catches foundation, electrical, and historic-compatibility issues before the application is filed.

Carport Conversion

Carport conversions in Pasadena face a specific challenge: most were built without slabs rated for enclosed living space, and many sit on sloped foothill lots where drainage and foundation depth vary block by block. Our permit set includes a structural assessment of the existing slab or a replacement specification, plus the full envelope upgrade to meet Pasadena’s energy code. We don’t pour concrete until the client has approved the scope and price in writing.

Garage Partition & Bathroom Add

Some Pasadena homeowners want to keep parking space and add a studio or bathroom within the existing garage footprint. This requires careful space planning to meet minimum ceiling heights, natural light requirements, and ventilation standards - especially in garages with low original rooflines common in the 1920s alley structures. We model the partition layout in our design phase so you see the square footage trade-offs before construction starts.

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Trusted Brands We Service in Pasadena

Ellery ADU Studio specifies and coordinates prefab and modular systems from Abodu, Cover, and Mighty Buildings within the same single-contract model we use for stick-built conversions. For Pasadena clients considering a modular path, we evaluate whether the manufacturer’s standard cladding and window packages meet historic-district compatibility requirements before the deposit is placed. Our crews are fluent in both site-built and systems-built construction, and we source Pasadena-compatible materials - wood windows, ignition-resistant siding, ember-resistant vents - through local suppliers with the turnaround times foothill permitting schedules demand.

Common Garage Conversion ADU Problems We See in Pasadena Homes

• Knob-and-tube wiring and 60-amp panels. We find active knob-and-tube in roughly half the pre-1940 Pasadena garages we open. It’s not grandfathered for a new ADU permit; the full rewire and panel upgrade to 200 amps is a code requirement, not an option. We price this during our initial inspection, not after demolition.
• Rotted post-and-pier foundations. The raised foundations under Pasadena’s alley garages sit close to grade and trap moisture from winter rains and summer irrigation. Posts soften at the base; piers crack. We document sill and post condition with photos before you sign, so foundation repair is a known line item.
• Historic Preservation Commission design-review denials. On contributing properties, vinyl windows, flat roofs, or smooth modern cladding trigger compatibility denials that add months and thousands in redesign fees. We research your property’s historic status before the first drawing and specify compatible materials from the permit application.
• VHFHSZ fire-code upgrades. North Pasadena addresses in the Very High Fire Hazard Severity Zone require ember-resistant attic vents, ignition-resistant exterior cladding, and defensible-space setbacks that standard garage conversions ignore. We verify your parcel’s fire zone status in pre-design and build those requirements into the written price.

Pricing for Garage Conversion ADU in Pasadena, CA

We Also Serve Cities Near Pasadena

Our crews work throughout the San Gabriel Valley and central Los Angeles County, including Pasadena, Alhambra, Glendale, Burbank, and North Hollywood. Each city carries its own permitting timeline and design requirements; we maintain current permit-tracker data for all five so your project schedule is based on actual department turnaround, not optimism.

FAQs - Garage Conversion ADU in Pasadena