
Luxury Remodeling in Ontario
Pools, outdoor living and ADUs planned around Ontario's historic review, pool setbacks and wind-blown alluvial sand.
Building in Ontario
Backyards, pools and ADUs for Ontario's historic districts and Ontario Ranch.
George and William B. Chaffey founded Ontario in 1882 as an irrigation colony, and its backbone was Euclid Avenue, a boulevard of twin roadways divided by a central mall that rises on a long, easy incline from the Southern Pacific tracks toward the mouth of San Antonio Canyon. The older city holds eight designated historic districts, where Craftsman bungalows stand near Mediterranean, Tudor and Victorian houses. To the south, the 13-square-mile Ontario Ranch occupies land the city annexed in 1999 from the former San Bernardino County Agricultural Preserve, where dairy farms had shaped the landscape since the early 1900s and are now giving way to master-planned neighborhoods. Beneath most of the city lies alluvial sand that the Safety Element treats as a wind-related hazard, so a backyard plan here weighs historic review, dust and wind during excavation, and exactly where a pool, its barrier fence and an ADU may sit on the lot.
Two eras share the city: the Chaffey brothers' original subdivision pattern, still intact around the historic downtown and Euclid Avenue, with early tracts such as College Park, subdivided into 48 lots in 1914, and Armsley Square, laid out in 1924, and Ontario Ranch to the south, where former dairy properties are being converted to master-planned neighborhoods. Development Code Table 6.01-1 sets the minimum traditional single-family lot at 18,000 square feet in the AR-2 district, 10,000 in RE-2 and RE-4, and 7,200 in LDR-5.
One team designs, permits and builds every project, and our own crews self-perform the work, so the people who plan your Ontario project are the people on site building it.
Part of our service area in San Bernardino County.
Local Conditions
What building in Ontario involves
Permits in Ontario
City of Ontario Community Development, Building Department
Under the Development Code's residential standards, a pool, spa or pond 1.5 feet deep or more cannot be built in a front yard, must sit at least 3 feet from side and rear property lines and must be enclosed by a decorative nonclimbable fence or wall at least 5 feet high, while diving boards, slides, waterfalls and decorative rockscapes need at least 5 feet from side and rear lines. ADU applications go to the Building Department electronically through the city's Citizen Portal Access, and the city's ADU handout caps a detached unit at 850 square feet for a studio or one bedroom and 1,000 square feet for two or more, generally at 16 feet tall, with 4-foot side and rear setbacks and 6 feet of separation between detached structures. Exterior alterations to historic buildings, including homes in the city's eight designated historic districts, need a Certificate of Appropriateness reviewed by Planning staff, the Historic Preservation Subcommittee and the Historic Preservation Commission, or a Planning waiver for minor alterations.
Permit details checked September 2026 against City of Ontario. Rules change, so we confirm them again for your parcel.
What we plan for here
- Pool setbacks and 5-foot barrier fencing
- Certificate of Appropriateness review in historic districts
- Wind and dust control during excavation
- Detached ADU sizing and 6-foot structure separation
The Safety Element describes the alluvial sand beneath most of Ontario as very susceptible to erosion, with strong winds driving it onto property, and its policies require dust-control best management practices on all excavation and grading and prohibit excavation and grading during strong wind conditions as defined by the Building Code, which brings the wind forecast into any dig schedule.
Because of the local topography and the nearby Cajon Pass, the Safety Element names Santa Ana winds as by far the city's greatest fire hazard, with increased risk in older portions of Ontario, although its 2025 CAL FIRE-based map shows no Fire Hazard Severity Zone inside city limits.
Much of the central and western city, roughly from Fourth Street south to Riverside Drive and west of Haven Avenue, lies inside the Safety Element's mapped zone of subsidence due to groundwater pumping, liquefaction is also listed among local hazards, and the city follows state guidelines and the California Building Code to decide when a project needs a geotechnical investigation.
Properties inside the Airport Influence Area of the LA/Ontario International Airport Land Use Compatibility Plan are subject to that plan's requirements under the Development Code, a check worth making alongside zoning before an addition or ADU is designed.
Neighborhoods we work in
- College Park
- Armsley Square
- Rosewood Court
- El Morado Court
- Euclid Avenue
- Ontario Ranch
Ontario Services
Everything we build in Ontario
Each page covers permits, costs and the build process for that work in Ontario.

Pool & Spa Remodeling in Ontario
We design and build pools and spas with our own crews, start to finish.

Backyard & Outdoor Living in Ontario
Outdoor living, hardscape, and curb appeal, designed and built to outlast the SoCal sun.

ADUs & Additions in Ontario
We design, permit, and build ADUs and additions that actually add value.
Also available in Ontario
Ontario Guides
Remodeling guides for Ontario
Local planning notes, costs and design direction for Ontario homeowners.
Whole-Home Remodel Sequencing: What to Do First
A whole-home remodel done in the wrong order costs 15 to 25 percent more. Here is the correct sequence, from structural and roof through to paint, and why each stage has to precede the next.
Read guideIndoor-Outdoor Living Conversions in Southern California
A 16-foot multi-slide door runs $18,000 to $45,000 installed. Here is how the full indoor-outdoor conversion works, from structural header to flush threshold to covered patio tie-in.
Read guideTarzana Outdoor Living: A Builder's Guide to South of the Boulevard Lots
Tarzana backyards run hot and deep. A working outdoor living build here (shade, hardscape, kitchen, lighting) typically lands between $85,000 and $220,000, and the ground drives most of the number.
Read guidePorter Ranch Backyard Transformation: Wind, Slope and What It Costs
A full backyard transformation in Porter Ranch runs $95,000 to $280,000. Wind exposure, slope, HOA review and fire-zone material rules shape the design before anything about style enters the conversation.
Read guideStart Your Project
Now booking design consultations in Ontario.
Tell us about your home and what you want from it. We call you back within one business day.
Licensed, bonded and insured · CSLB #1119054 · Veteran-owned and family-operated