







A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateADU Company in Pasadena, CA
An ADU in Pasadena typically runs between $180,000 and $420,000 depending on whether you convert a detached garage, build a backyard cottage, or add a second story above an existing structure. What makes Pasadena jobs different is the housing stock itself: Craftsman homes from 1905 to 1930, narrow lots, detached garages built for Model Ts, and a city permitting culture that is simultaneously fast-moving and exacting about design. Benson ADU Pasadena handles the planning, permits, and construction so you know the written price before any work starts. Call (626) 658-3527 for a free estimate.
Why Pasadena Homes Are Different

Pasadena is dominated by early 20th-century Craftsman, Spanish Colonial Revival, and English Tudor homes, many on narrow lots where the detached garage predates the homeowners’ grandparents. Those garages are often the single best ADU opportunity in the city, but they are rarely built to modern code, and bringing a 1920s structure up to today’s seismic and energy standards is a real engineering task, not a weekend paint job. Post-war ranch houses in neighborhoods like Hastings Ranch and Upper Hastings Ranch are the other common canvas, and there a backyard cottage usually fits without much drama.
The climate shapes every decision too. Hot, dry summers mean ADUs need cross-ventilation, shade, and drought-tolerant landscaping rather than heavy insulation. Mild, wet winters mean drainage and foundation moisture control matter more than snow load. And if you’re in the wildfire-adjacent foothill areas above the 210, defensible space and fire-resistant cladding become part of the permit conversation. The “Pasadena 100” rule, the city’s stated goal of permitting 100 ADUs per year, keeps plan checks moving relatively fast, but historic districts like Bungalow Heaven carry strict design review. There, an ADU must match the main home’s roof pitch and window muntins, which is exactly the kind of detail that separates a smooth approval from a six-month delay.
Our Main Pasadena Services
Pasadena homeowners call us most about two things: building a new ADU from the ground up and converting or expanding the home they already live in. Here is what each involves in Pasadena.
ADU Builders in Pasadena
Most Pasadena ADU projects take one of three paths: converting a detached garage, building a backyard cottage, or adding a second-story unit above the existing home. Each carries different site constraints. A garage conversion on a narrow Bungalow Heaven lot depends on whether the existing foundation and roofline can be brought up to code without rebuilding from scratch. A backyard cottage asks a simpler question: where does the setback line actually fall, meaning how far the structure must sit from the property line. We carry prefab options from Abodu and Cover for homeowners who want a faster, more predictable build, alongside site-built construction when the lot or historic district demands a custom footprint. ADU Builders in Pasadena covers the full scope and pricing.

Home Addition Contractor in Pasadena
A home addition in Pasadena usually means expanding the footprint of a house that was never designed to grow. On the narrow lots common throughout the city, a side or rear addition must respect setbacks while preserving access to the detached garage. On hillside properties in the San Rafael Hills, foundation work gets more involved and the structural engineering is not optional. We write the plan and the price before any work starts, and our 365-Day Done Right Promise covers the build for a full year after completion. Home Addition Contractor in Pasadena breaks down the process and the numbers.

Room Addition Contractor in Pasadena
A room addition is the smaller cousin: a single bedroom, a home office, a family room bumped out from the back wall. In Pasadena’s post-war ranch neighborhoods, this often means extending an exterior wall and re-roofing a section of the house. In older Craftsman homes, matching the existing roofline and siding matters both for curb appeal and for the historic review process. We handle permits, foundation work, framing, and finish work with a written price before the first shovel turns. Room Addition Contractor in Pasadena has the full scope.

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.
- 4
You approve before work beginsNothing starts until you say go.
Brands We Service in Pasadena
We build with prefab systems from Abodu, Cover, and Dvele, and we clad with James Hardie materials where fire resistance or durability calls for it. Parts and materials are sourced through our local supply chain, so a Pasadena project does not wait on a delivery from three states away. See the full lineup on our brands page.
Pricing for ADU Company in Pasadena, CA
| Service | Typical range in Pasadena |
|---|---|
| Garage conversion ADU | $180,000 – $260,000 |
| Backyard cottage ADU (site-built) | $250,000 – $420,000 |
| Backyard cottage ADU (prefab, e.g. Abodu or Cover) | $200,000 – $350,000 |
| Second-story ADU above existing home | $300,000 – $500,000+ |
| JADU (junior ADU, converted from existing space) | $80,000 – $150,000 |
| Home addition (single room, ground level) | $120,000 – $220,000 |
| Home addition (multiple rooms or second story) | $250,000 – $450,000+ |
| Room addition (bedroom or office bump-out) | $90,000 – $180,000 |
What pushes a Pasadena ADU toward the top of those ranges is usually one of three things: a historic district review that requires custom window and roof detailing, a hillside lot that demands deeper foundations and retaining work, or an older garage whose foundation and framing need a full rebuild before conversion can begin. Whatever the number ends up being, you get it in writing before any work starts, and it does not change at the door.
Neighborhoods We Serve in Pasadena
We work across the full city, from the flatlands to the foothills. Response time for estimates and site visits across the Pasadena area is typically within a few business days.
- Bungalow Heaven
- Madison Heights
- Hastings Ranch
- San Rafael Hills
- Linda Vista
Service Area – Cities Near Pasadena
Our Pasadena-based crews also serve homeowners in the surrounding San Gabriel Valley and West San Gabriel communities. If you are just across the city line, we can usually help without skipping a beat: San Marino, CA, South Pasadena, CA, Altadena, CA, and San Gabriel, CA.
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 About ADU Company in Pasadena

In most cases you can get a written estimate within a few business days of calling, and once the permit is approved, construction on a prefab ADU typically starts within four to eight weeks depending on the brand and current city plan check volume. Call (626) 658-3527 and we will confirm the timeline for your specific street.
Yes. Pasadena’s amnesty program offers a one-time window for owners of unpermitted units built between 2017 and 2022 to bring them into compliance with reduced fees and a streamlined inspection path. We prepare the plans, coordinate the inspections, and manage the correction work on our end. Call for a free assessment of your specific property.
It can. In districts like Bungalow Heaven, ADUs must match the main home’s roof pitch, window muntins, and exterior materials, which can add design and materials cost compared to a standard build. We factor that into the written price before any work begins, so there is no surprise line item later. Call (626) 658-3527 for an exact quote for your lot.
Ready to get a real number for your Pasadena ADU or addition? Call (626) 658-3527 to schedule your free estimate, or home to see everything we build.
What happens when you call
- 1A real person answersNo phone trees - talk to a local adu pro.
- 2You get an upfront price rangeHonest numbers before anyone is dispatched. No surprises.
- 3We come out and measureLicensed & insured, at a time that suits you - the visit and the quote are both free.
- 4You get the price in writingLine-itemed, yours to keep, and nothing starts until you say go.
What Pasadena Customers Say
"Fixed quote and clear change orders approved by text."
- Trina M."Photos of each milestone, which I loved. Slab, framing, roof dry-in, each one came with a few pictures by text."
- Gwen D."Garage conversion into a guest suite. I could see the permit status in the app, which made it painless."
- Rick F.




