A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateFast, Reliable Home Addition Contractor Across Richmond
If you’re planning a home addition in Richmond, you want a real number before anyone swings a hammer. A second-story addition over a detached garage in the flatlands typically runs $180,000 to $310,000 when built to coastal spec. A rear-yard ADU conversion with ADU Builders - Richmond usually lands between $95,000 and $160,000. We write the price down before work starts, every time. Call (707) 760-0502 to talk through your lot, your budget, and what Richmond’s fog and soil mean for your build.
We know Richmond’s streets, its housing stock, and the specific way salt air eats standard building materials here. That local knowledge changes what we specify on every job, from fasteners to siding to window frames. If you’ve had a contractor walk off, change a price, or leave a mess behind, you’re not alone here. We built Lodgewick ADU San Francisco to answer that experience directly.
Why Lodgewick ADU San Francisco Is Richmond’s Preferred Home Addition Contractor Company
Lodgewick ADU San Francisco is the ADU company of the Kingswell family. We’re a Home Addition Contractor that specializes in accessory dwelling units, garage conversions, second-story additions, and bump-outs. Founded in 2010, we’ve spent fifteen years learning what works in Bay Area neighborhoods, and Richmond’s older single-family lots are some of the most interesting and challenging we see.
Our reputation in Richmond rests on one thing: we put every commitment in writing before the first day of work. That’s The Kingswell Guarantee, and it means a written price, a defined arrival window, a clean job site, and a written guarantee on every project. If the work isn’t right, we come back and make it right, free, within the 365-day guarantee period. That promise is printed and delivered with every contract.
Led by Russ Delmar, our crews work in Richmond weekly. We answer our phones with a live person twenty-four hours a day, seven days a week. No voicemail loops. When you call about your build, you talk to someone who knows your job.
Second Story Addition Contractor in Richmond
A second story addition in Richmond means building upward instead of outward, and on the city’s deep, narrow lots, that’s often the only direction that makes sense. We’re a Second Story Addition Contractor serving Richmond neighborhoods from Point Richmond to the Hilltop area, and we’ve learned that the structural and material choices on these jobs matter more here than in inland Contra Costa.
The biggest cost driver on a Richmond second-story job is marine-grade specification. Salt-laden fog rolling off San Francisco Bay settles on everything. Standard electro-galvanized roofing nails rust out in three to five years; we specify hot-dip galvanized ring-shank nails and 316 stainless steel connectors at ledgers and beams. Fiber-cement siding like James Hardie holds paint and resists moisture far better than wood lap in this microclimate. A second-story addition in Richmond typically runs $185 to $310 per square foot depending on whether the lower structure needs seismic or foundation work.
What the coastal spec means in dollars
The same second-story addition built to inland standards might save you eight to twelve percent on the front end. That savings evaporates when window frames pit, roof nails corrode, and siding wicks fog moisture into the sheathing. We quote the Richmond spec up front so the number you see is the number that keeps you dry for decades.
Second-story work on detached garages
Many Richmond lots have detached rear garages with shallow concrete pads and wood framing from the 1940s and 1950s. Before we build up, we check the pad, the framing, and the existing electrical feed. We’ve found cloth-wrapped wiring and corroded roof nails on nearly every older garage we’ve opened near Cutting Boulevard and beyond. Rebuilding the lower walls is sometimes necessary; when it is, we tell you before the estimate, not after.
Garage Addition Contractors in Richmond
Garage conversions are the most common home addition in Richmond’s central flatlands, where detached rear garages sit on long, deep lots. We’re Garage Addition Contractors who have worked on many of these conversions, and the first thing we check is the siding. Richmond’s older garages often carry asbestos siding or adhesive, and cutting into it without testing triggers abatement delays and stop-work orders that no homeowner wants.
A garage-to-ADU conversion in Richmond typically runs $95,000 to $160,000, depending on whether the pad needs replacement, the roof needs full re-sheathing, and the electrical panel can handle the new load. Most of these garages were never wired for living space, so a subpanel upgrade is common. We also see shallow concrete pads that need thickened footings or full replacement before framing can start.
Asbestos and abatement before the build
If your garage was built before 1980, we test before we cut. The cost of testing is small; the cost of stop-work orders and abatement mid-project is not. We include testing in our written estimate when the age of the structure calls for it.
Coastal fasteners on rear-yard work
Any garage conversion in Richmond’s fog zone needs corrosion-resistant hardware at every exterior connection. We use stainless joist hangers, hot-dip galvanized nails at roof sheathing, and sealed joints where framing meets existing stucco. These choices cost more, but they’re the difference between a ten-year build and a thirty-year build.
Trusted Brands We Service in Richmond
We work with established ADU brands and materials suppliers including Abodu, Tuff Shed, and James Hardie. For Richmond homeowners considering a prefab ADU as part of a rear-yard addition, Abodu’s panels arrive engineered and ready to assemble on site, which cuts framing time significantly. Tuff Shed structures work well for storage units and workshop conversions. And James Hardie fiber-cement siding is our standard exterior cladding recommendation in Richmond’s salt-fog environment. We stock common replacement parts and materials for these brands locally, which means less waiting when a change order or repair comes up mid-project.
Common Home Addition Contractor Problems We See in Richmond Homes
- Rusted roofing nails on older additions. Bay fog corrodes standard electro-galvanized nails within three to five years, causing shingle lift and winter leaks. We open roofs on Richmond additions and find this on most pre-2000 builds.
- Asbestos siding or adhesive in pre-1980 garages. Cutting into it without testing releases fibers and triggers abatement stop-work orders. We test first, every time, and build the abatement cost into the written estimate.
- Soil settlement on rear-yard additions near old rail and refinery land. Richmond’s industrial legacy means some lots need a Phase I environmental screen and compaction testing before foundation work. Skipping this leads to sinkage cracks in stucco corners within two seasons.
- Undersized electrical panels on 1920s-1960s homes. Adding a kitchen, bathroom, or second story means new circuits, and many Richmond panels are at capacity. We upgrade the panel before the walls go up, not after the drywall is hung.
Pricing for Home Addition Contractor in Richmond, CA
Here are the ranges we see for common Richmond home addition projects in 2025. These are real numbers for planning, not placeholders:
| Project Type | Typical Richmond Range | What Moves the Price |
|---|---|---|
| Garage-to-ADU conversion | $95,000 – $160,000 | Pad replacement, panel upgrade, asbestos testing, coastal fasteners |
| Second-story addition | $185 – $310 per sq ft | Lower-wall structural work, marine-grade hardware, roof complexity |
| Bump-out addition | $70,000 – $120,000 | Foundation depth, roofline integration, window spec |
| Bathroom addition | $45,000 – $80,000 | Drain line access, waterproofing, ventilation |
| Sunroom addition | $55,000 – $100,000 | Glazing spec, salt-fog coatings, thermal breaks |
Every estimate we write is a fixed, written price. No change orders at the door, no “discovered conditions” upcharge without your sign-off first. Call (707) 760-0502 to schedule a free estimate and we’ll walk your lot together.
One thing that surprises Richmond homeowners is the price gap between a coastal-spec job and an inland-spec job. The same second-story addition in Antioch or Concord runs about eighteen percent less than the Richmond build because inland contractors can use standard fasteners and basic window frames. In Richmond, that cheap spec fails fast. A re-roof done with electro-galvanized nails needs attention before year five. Marine-grade hardware costs more up front, but you won’t be chasing rust streaks or loose siding before the ten-year mark.
We Also Serve Cities Near Richmond
Our crews work throughout the East Bay and North Bay. We regularly serve Corte Madera, San Rafael, Emeryville, and Sausalito, plus the neighborhoods in between. If you’re just outside Home Addition Contractor in Richmond territory, call and ask, we’ll likely be there this week.
Serving Richmond, CA - Our Local Coverage Area
We’re based in the Richmond 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 Home Addition Contractor in Richmond
Because Richmond’s salt-laden fog requires marine-grade fasteners, 316 stainless steel connectors, and sealed stucco joints, while Pinole sits farther from the bay and has less salt exposure. The materials add roughly twelve to eighteen percent to the build. But the inland-spec version loses that savings within a decade as nails rust and siding wicks moisture. Call (707) 760-0502 for an exact quote, we’ll show you the line-item difference.
Asbestos siding or adhesive, cloth-wrapped electrical feeds, and shallow concrete pads that were poured for car storage, not living space. We test before we cut, upgrade the panel before drywall, and thicken or replace the pad before framing. These aren’t surprises to us, they’re line items in the written estimate.
Sometimes, but rarely on garages built before 1960. The lower walls and pad need to be checked for shear capacity, moisture damage, and corrosion before we’ll sign off on adding load above. We’ve done it on well-maintained garages, and we’ve also told owners the lower walls need to come down. The honest answer comes after an inspection, and it’s free to find out. Call (707) 760-0502.
We specify continuous mechanical ventilation, vapor-open wall assemblies, and exterior insulation that lets vapor dry outward. Richmond’s fog keeps relative humidity high from June through September, so a sealed-up ADU without active air exchange will smell damp within a year. We plan for that from the start, not after the first winter.
Former rail-served and industrial land can have fill dirt, buried debris, and contaminated soil that requires a Phase I environmental screen and compaction testing before foundation work. Sinkage cracks in stucco corners are the classic sign of a build that skipped this step. We include soil review in our written estimates for any rear-yard addition in central Richmond.
Call Lodgewick ADU San Francisco for Your Richmond Addition
You’ll get a real person on the phone, a written price before any work starts, and a written guarantee that lasts 365 days. If the work isn’t right, we come back and make it right. Led by Russ Delmar, our Richmond crews know this city’s housing stock, its fog, and its soil. Call (707) 760-0502 today to schedule your free estimate.
Written by Russ Delmar, Owner at Lodgewick ADU San Francisco, serving Richmond and the surrounding Bay Area.
