







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 Home Gardens
Home addition costs in Home Gardens run $145,000 to $380,000 for a new primary suite, bathroom addition, or garage conversion, depending on square footage, site conditions, and how much of the existing structure you’re tying into. County permitting through Riverside County, not a city building department, is the single biggest factor most Home Gardens homeowners miss when they start budgeting. At Benson ADU Builders, we scope that in from the first conversation and put the price in writing before any work begins. Call (903) 568-7222 for a free estimate on your project.
Why Benson ADU Builders Is Home Gardens’s Preferred Home Addition Contractor Company

Most Home Gardens homeowners we talk to have never done a permitted addition before, and the county process catches them off guard. Home Gardens is unincorporated Riverside County, which means plan-check comments and inspection scheduling run on county timelines, not a city counter. Our team has walked dozens of Home Gardens lots along Magnolia Avenue, Big Springs Road, and the streets off Campbell Avenue. We know what the county plan-checker looks for before we submit, so the first submittal is clean instead of a three-week ping-pong match.
Every project gets a written price before work starts and a 365-Day Done Right Promise in writing. Troy Eastman leads our crews, and the technicians who show up at your door in Home Gardens are background-checked and in uniform. We also answer the phone around the clock. No voicemail loops when you’re waiting on an inspection update.
Home Gardens homeowners keep bringing us back for a simple reason: we put numbers on paper and we stick to them. The Relay Visibility Guarantee isn’t a slogan. It’s the written price, the written guarantee, and a free second visit if a covered repair fails within a year.
Garage Addition Contractors in Home Gardens
Garage Addition Contractors in Home Gardens handle two very different jobs: converting an attached or detached garage into finished living space, or building a new garage with a bonus room above it. On Home Gardens lots, where many homes sit on half-acre parcels carved out of the original tract farms, a detached garage conversion often makes more financial sense than a full second story. You’re working with an existing foundation, existing roofline, and usually existing electrical service, which trims the budget to $95,000 to $210,000 depending on whether you need a bathroom added and how much the county requires you to bring the structure up to current code.
Garage Conversions and County Septic Reviews
The piece nobody budgets for on older Home Gardens lots is the septic capacity review. Streets like Magnolia Avenue still have homes on septic systems, and Riverside County will flag an addition that adds a bedroom if the existing leach field can’t handle the assumed occupant load. That can add $18,000 to $35,000 for a septic upgrade, and it’s not optional. We flag it during the estimate walk, not after the concrete is poured.
What a New Garage Addition Actually Covers
A new garage build in Home Gardens includes slab or stem-wall foundation, framing, roof tie-in or standalone trusses, electrical subpanel where required, and matching exterior cladding. We build with James Hardie siding on most Home Gardens garage additions because it holds up against the Inland Empire’s dry heat without fading like vinyl and without the repaint cycle stucco demands. Budget $130,000 to $250,000 for new construction with a finished interior.
Bathroom Addition Contractor in Home Gardens

A Bathroom Addition Contractor in Home Gardens needs to think about more than tile and fixtures. Many mid-century Home Gardens homes were built with one bathroom and a 100-amp electrical panel, which means a second full bath usually triggers a panel upgrade and sometimes a water-heater upsizing. A typical 40 to 70-square-foot bathroom addition in Home Gardens runs $55,000 to $95,000 when it’s tucked into existing floor space, and climbs to $110,000 to $160,000 when you’re extending the footprint and cutting new foundation.
Bathroom Additions That Use the Existing Footprint
Bumping a hallway bathroom out into a large laundry room or dead hallway space is the most cost-effective bathroom addition we do in Home Gardens. The roof line stays intact, the foundation already exists, and plumbing rough-in usually only needs a short branch line. You’re into fixture selections and finishes within a couple of weeks rather than waiting on a soil report.
Full Bath Additions That Extend the House
When you add a true primary bathroom off the back of the house in Home Gardens, we’re pulling a county permit, cutting a foundation tie, and often re-roofing that section. Riverside County will require a setback review, and on lots where the existing home already sits close to the property line, a variance can add 30 to 60 days. That timeline is real, and it’s better to know it before you plan a move-in date around it.
Trusted Brands We Service in Home Gardens
Home Gardens homeowners want to research what they’re buying before they sign a contract, and we encourage that. We’re authorized to build with Dvele and Boxabl pre-fab systems, and we spec James Hardie cladding on most exterior work because it performs in Riverside County’s heat. Our Home Gardens crews keep common trim, flashing, and tie-in materials stocked locally, so a missing corner board doesn’t stall your framing inspection for a week. If you want to look up the products by name, you can. That’s the point of putting a brand on the line item.
Common Home Addition Contractor Problems We See in Home Gardens Homes
- Wrong jurisdiction on the permit application. A homeowner or an out-of-area contractor files with the City of Corona or Riverside, gets bounced, and loses two weeks of plan-check time before the county even opens the file. Home Gardens is unincorporated, which means every permit application goes through Riverside County’s building department, and that changes the submittal checklist, fees, and inspection scheduling.
- Septic capacity triggers nobody priced. Older Home Gardens properties on septic, especially along Magnolia Avenue and the side streets branching off it, face Riverside County septic capacity reviews when an addition adds bedrooms. A $25,000 septic upsizing mid-project is the kind of surprise that kills a budget and breeds resentment.
- Slab foundations that don’t match the record drawings. Many Home Gardens homes were built between the 1940s and 1970s, and as-built drawings often don’t reflect actual foundation dimensions. We survey the existing foundation before we lock the price, because a structural tie-in that wasn’t in the original bid is a five-figure change order.
- Roofline tie-ins quoted sight unseen. A Home Gardens addition that ties into a mid-century roofline with non-standard framing needs heavier beams and sometimes a partial re-roof. Contractors who quote from square-foot averages leave that out, then hand you a change order after the roof is opened. Our written price includes the tie-in scope before work starts.
Pricing for Home Addition Contractor in Home Gardens, CA
Here are the honest ranges for Home Gardens, not national averages: a primary suite addition (340 to 450 square feet) runs $145,000 to $210,000. A bathroom addition runs $55,000 to $160,000 depending on footprint. A garage conversion sits at $95,000 to $210,000. A second-story addition in Home Gardens is the priciest option at $280,000 to $380,000 because the county requires structural engineering on the existing lower floor. These numbers assume standard finishes and no septic or panel surprises. Your final number comes from a free on-site walk. Call (903) 568-7222 for an exact quote in writing.
We Also Serve Cities Near Home Gardens
Our crews serve Home Gardens and the surrounding communities including Home Gardens plus Los Angeles, Long Beach, Anaheim, and Riverside. If your property sits just outside the Home Gardens boundaries but still falls in Riverside County or the nearby metro area, we’ll confirm coverage when you call. And our Home Addition Contractor team supports every project with the same written pricing and Done Right Promise.
Serving Home Gardens, CA - Our Local Coverage Area
We’re based in the Home Gardens 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 Home Gardens
Riverside County permit. Home Gardens is unincorporated, so there’s no city building department to file with. All addition plans, structural reviews, and inspections run through Riverside County, which changes the submittal checklist and the inspection scheduling process compared to working in neighboring Corona or Riverside city limits. Call (903) 568-7222 and we’ll confirm your parcel’s exact jurisdiction before anything gets filed.
Yes, and in Home Gardens it’s often the smartest dollar-per-square-foot move because the foundation, roof, and some electrical are already there. A garage conversion typically runs $95,000 to $210,000 depending on size and finish level. The two variables that move the number are whether you add a bathroom and whether Riverside County requires seismic or septic upgrades. We’ll walk the garage and give you a written price before you decide.
Plan for 5 to 9 months for a full addition in Home Gardens, with 6 to 10 weeks of that in county plan check and permitting alone. Smaller jobs like a garage conversion can finish in 4 to 6 months. Riverside County’s unincorporated timelines run slower than most city counters, which is why we submit complete plans the first time instead of gambling on resubmittals. Call (903) 568-7222 for a project-specific calendar.
In Home Gardens, the usual price-movers are septic capacity upgrades on older half-acre lots, foundation conditions that don’t match the as-built drawings, and county-required structural upgrades on mid-century homes. That’s why our written price includes a foundation walk and septic check before you sign. We don’t hand you a change order for something we should have caught in the estimate. Call (903) 568-7222 for a free estimate that accounts for these factors up front.
Both. We’re authorized to build with Dvele and Boxabl pre-fab systems, and we also do fully stick-built additions. Pre-fab shells can shave weeks off the framing schedule in Home Gardens, which matters when you’re waiting on a county inspection cycle. We’ll show you brand options, pricing, and real timelines for each, then you choose. Call (903) 568-7222 to talk through the trade-offs.
Key Takeaways
- Home Gardens additions are permitted through Riverside County, not a city building department.
- Written price before work starts, always. No verbal estimates that shift later.
- 365-Day Done Right Promise on every project, in writing, with a free second visit if a covered repair fails.
- Upfront pricing ranges: $55,000 to $380,000 depending on scope and site conditions.
- Septic capacity and mid-century foundation conditions are the two biggest local cost movers.
Ready to get a real number for your Home Gardens addition? Call Benson ADU Builders at (903) 568-7222 for a free on-site estimate. Troy Eastman and our Home Gardens crews will walk the property, check the foundation and septic if applicable, and hand you a written line-item price before you commit. That’s the only way we work.
Written by Troy Eastman, Owner at Benson ADU Builders, serving Home Gardens homeowners with written pricing and the 365-Day Done Right Promise.


