







A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateADU Company in Bonita, CA
An ADU in Bonita means something different than it does in most of San Diego County. Here, lots run half an acre to two acres, many homes sit on septic, and a chunk of the community still keeps horses. So an accessory dwelling unit – a small, fully independent home on your existing property – is less about squeezing extra square footage onto a tight city lot and more about fitting a second home into a semi-rural landscape without losing the space that made you buy the property in the first place. Lodgewick ADU San Diego handles that balancing act daily, with a written price before any work starts and the Kingswell Guarantee on every project. Call (619) 376-2760 to talk through your lot.
Why Bonita Homes Are Different

Bonita’s housing stock leans heavily toward single-family ranch homes and Spanish-influenced builds from the 1950s through the 1980s. Most sit on oversized lots in neighborhoods like Bonita Woods and Bonita Highlands, where mature landscaping and horse-keeping areas are part of the appeal. That changes how we approach an addition or a garage conversion: we’re not just working around a house, we’re working around a property.
The big variable here is septic. A meaningful number of Bonita properties run on private wells and septic systems rather than city sewer. Adding an ADU – a second home with its own bathroom, kitchen, and laundry – often means upgrading or expanding that septic capacity before a foundation gets poured. It’s a cost and a permitting step homeowners in sewered areas never think about, and it’s one of the first things we check when we walk a Bonita lot.
Climate plays a role too. Summer highs routinely push past 90°F, and inland sun exposure is real. A well-planned Bonita ADU needs cross-ventilation, reflective roofing, and window placement that doesn’t turn the unit into an oven by 3 p.m. Those aren’t afterthoughts here; they’re design decisions made in the first week of planning.
Our Main Bonita Services
Most Bonita homeowners call us about one of three things: building a new detached ADU, converting an existing garage, or expanding the main house. Each has its own page with pricing, timelines, and local specifics.
Home Addition Contractor in Bonita
Adding onto a Bonita house usually means extending a ranch layout or building up over a garage, and the job has to respect the original architecture rather than fight it. Because many Bonita homes were built before modern energy and seismic codes, any addition triggers retrofitting on the existing structure – new shear walls, upgraded electrical, better insulation. Our crews handle that scope as part of the written price, not as a surprise change order halfway through. Home Addition Contractor in Bonita covers full pricing and what a typical addition costs here.

Garage Conversion Contractor in Bonita
A garage conversion in Bonita is usually the fastest path to a rentable or multi-generational unit, because the shell already exists. But Bonita garages from the 1960s and 1970s often need full electrical rewires, new slab insulation, and seismic bracing before they can legally become living space. Septic capacity is the other recurring question – if your system was sized for a three-bedroom house, adding a full bathroom in the garage may push it over. Garage Conversion Contractor in Bonita walks through the steps and the real numbers.

ADU Builders in Bonita
Detached ADUs on Bonita’s larger lots give us room to work without disturbing the main house, which is a real advantage over tighter cities. Projects here often pair a new ADU with preserving mature trees, keeping horse access open, or maintaining sightlines across the property. The septic and well considerations are front and center for detached units, since a new ADU almost always means a larger tank or an expanded leach field. ADU Builders in Bonita has full pricing, timelines, and what to expect from permitting.

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 Bonita
We work with a range of prefab and panelized ADU manufacturers, matching the system to the lot, budget, and timeline. In Bonita, we most often quote Boxabl for its compact footprint, Plant Prefab for larger custom layouts, and James Hardie siding for durability in the inland sun. See our brands for the full list and what each one does best.
Pricing for ADU Company in Bonita, CA
| Project type | Typical range in Bonita |
|---|---|
| Detached ADU (1 bed, 1 bath, ~450 sq ft) | $180,000 – $260,000 |
| Detached ADU (2 bed, 2 bath, ~750 sq ft) | $275,000 – $380,000 |
| Prefab ADU (Boxabl Casita, turnkey install) | $98,000 – $145,000 |
| Garage conversion (full living unit with kitchen) | $110,000 – $185,000 |
| Garage conversion (studio, no kitchen) | $75,000 – $115,000 |
| Home addition (primary suite, ~400 sq ft) | $160,000 – $230,000 |
| Home addition (family room extension, ~300 sq ft) | $120,000 – $175,000 |
| Septic system upgrade (for ADU addition) | $18,000 – $38,000 |
| Site work and foundation (sloped or cleared lot) | $8,000 – $24,000 |
| Permit and plan set fees (Bonita building dept) | $6,000 – $14,000 |
Septic upgrades and slope work are the two line items that push Bonita ADU projects above county averages. Every estimate we give is a written price before work starts – no change orders at the door, no “we discovered something” price adjustments mid-project.
Neighborhoods We Serve in Bonita
We work across Bonita, from the equestrian-zoned streets in the east to the tighter pockets near the 805. Our crews are local to the area, and scheduling is coordinated through the San Diego office with crews dispatched to Bonita jobs directly. Most estimates happen within a few days of your call.
- Bonita Woods
- Bonita Highlands
- Bonita Glen
- Emerald Ranch
- Rohr Park area
Service Area – Cities Near Bonita
While most of our work stays in Bonita, we also serve homeowners in nearby communities including National City, CA, Chula Vista, CA, Lemon Grove, CA, and La Mesa, CA. If you’re just outside Bonita and wondering if we’ll come to your street, call and ask – the answer is usually yes.
Serving Bonita, CA - Our Local Coverage Area
We’re based in the Bonita 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 Bonita

Most Bonita homeowners get an in-person estimate within three to five business days of calling. We walk the property, check existing septic records, talk through what you’re trying to do with the extra space, and then put a written price in your hands. Call (619) 376-2760 to get on the schedule.
Usually yes, unless your existing system was oversized for the original house. We review your septic records and have the system inspected as part of the estimate, so you know the real number before committing to anything. It’s one of the biggest cost variables on Bonita lots, and we flag it early rather than letting it surprise you later.
In many Bonita neighborhoods, county design review expects the ADU to respect the character of the existing house and the surrounding lots. That doesn’t mean identical – it means compatible rooflines, setbacks, and materials. We handle that during design, so the ADU looks like it belongs on the property instead of looking dropped in.
No. The price you sign is the price you pay, unless you ask us to add something mid-project. That’s the Kingswell Guarantee, and it’s in writing on every Bonita project before the first nail is driven. If something isn’t done right, we come back and fix it – that’s also in writing, good for 365 days after completion. Call (619) 376-2760 to talk through your project and get a real number.
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 Bonita Customers Say
"Quality work on a home addition. It did run a few weeks longer than the original estimate, mostly waiting on the city for inspections, which they explained. The build itself was done right."
- Marcus Delgado"Added a suite for my dad. They walked us through every cost before a hammer swung and stuck to it. The written price is what we paid, no change orders."
- Ingrid Salazar"Detached unit in the backyard for rental income. They handled design and permits and gave me a real schedule. Came in close to on time and exactly on the written price."
- Benjamin Stahl





