ADU Builder · Pasadena
Backyard cottages and garage conversions designed to sit naturally among Pasadena’s Craftsman homes. Permits through the City of Pasadena, construction by our own crews.
ADU Builder in Pasadena
Pasadena was platted with generous lots, which makes it one of the best ADU cities in LA County. Maybe your backyard cottage becomes a rental. Maybe it keeps your parents close, or gives a grown kid a real front door. On a street of Craftsman bungalows, it also has to look like it was always there. That is design work we take seriously.
Athenian Builders Group is a licensed California contractor (CSLB #1045030) that designs and builds ADUs across Pasadena with its own crews. You get a fixed price in writing, a firm timeline, and a 2-year workmanship warranty. See our full ADU construction services.
Permits
Pasadena runs its own planning and building department, so ADU permits go through the City of Pasadena Permit Center, not LADBS, and the city applies its own ADU standards. We prepare the drawings, manage the submittal, and coordinate every inspection through final sign-off. The process stays on our plate, not yours.
Transparent Pricing
These are real 2026 ranges for the LA area. Where you land depends on size, your lot, and the finishes you choose. After a free on-site visit, you get a fixed, itemized price, line by line.
| ADU Type | Typical Size | Typical Cost (2026) |
|---|---|---|
| Garage Conversion | 300–500 sq ft | $100k – $180k |
| Junior ADU (JADU) | up to 500 sq ft | $90k – $160k |
| Attached ADU | 400–800 sq ft | $180k – $320k |
| Detached New-Build | 500–1,200 sq ft | $250k – $450k |
Typical ranges for 2026, not quotes. Financing is available for qualified homeowners: see remodel financing options. Considering a smaller in-home unit? See our Junior ADU page.
Estimated project cost
Why Athenian
Most “ADU builders” are design shops or brokers who sub the construction out. We’re a team that does it all in-house: we design it, pull the permits, and build it with our own crews. That means one point of contact, a fixed itemized price before we start, a firm timeline in writing, and a written 2-year workmanship warranty on everything we build in Pasadena.
Questions
Yes, all of it. From Bungalow Heaven to the Arroyo, we design and build detached ADUs, garage conversions, and JADUs across Pasadena, with our own crews on every job.
Pasadena is its own city, so ADU permits go through the City of Pasadena Permit Center under the city’s own ADU standards, not LADBS. Athenian Builders Group manages the entire process, from drawings through final inspection.
It depends on the type and size. A garage conversion typically runs $100k–$180k, while a detached new-build lands between $250k–$450k. You get a fixed, itemized price after a free on-site walkthrough.
Most of our ADUs finish in 3 to 5 months of construction. Pasadena’s plan review adds lead time before that, and type and size move the schedule. You get a firm timeline in writing before construction starts.
Start with a free on-site feasibility visit. We walk the lot, check what fits, and hand you a fixed, itemized price for your Pasadena ADU. Call (310) 857-2520. You’ll know the number before we break ground.
Takes about a minute. We reply the same business day and set up a free on-site visit.
