ADU Builder Ontario

Beautiful ADUs in Ontario and Beyond

ADUs Designed Better. Built Smarter.

Why Choose LADU for ADU Builder Services in Ontario?

LADU is an architect-led ADU contractor and one of the most trusted builders in Ontario for homeowners seeking a streamlined path from concept to keys.

As a local builder and contractor team, we focus on accessory dwelling unit solutions that respect neighborhood character while unlocking property potential.

Whether you are a homeowner planning a detached backyard cottage or a garage ADU, our Ontario experts make building an ADU predictable with clear pricing, accurate timelines, and attentive project management.

Why Adding an ADU in Ontario Is a Smart Move

An accessory dwelling unit (ADU) is a compact, code-compliant home on the same lot as a primary residence, and in Ontario, California, ADUs play a vital role in creating affordable housing and flexible living space.

With state legislation and local building codes designed to encourage ADUs, building an ADU is a high-impact way to generate rental income, support multigenerational living, and expand usable living space.

LADU Makes Building an ADU in Ontario Easy

Our architect-led process covers every step, from feasibility analysis and site planning to permit strategies and construction coordination, so that your ADU project stays on budget and on schedule.

Our team's expertise spans design styles and unit types tailored to Ontario lots and the surrounding Inland Empire context, ensuring your dream ADU complements your home and meets every permit requirement.

Local ADU Expertise in Ontario

Ontario homeowners benefit from our deep understanding of California building codes, local plan-check workflows, and the unique zone overlays that can affect setbacks, height, and parking.

From the first site walk to the final inspection, we plan for utility connections, floor area allocations, and structural requirements, simplifying each permit submission and any needed resubmittal.

ADU Services Offered in Ontario, California

Expanding your property with an accessory dwelling unit in Ontario requires smart planning, permitting expertise, and thoughtful design. Our comprehensive services guide you from initial concept to construction, ensuring your ADU adds value, comfort, and functionality to your home.

ADU Design

Our ADU Design Services provide detailed, permit-ready plans including floor layouts, elevations, sections, and energy compliance notes.

We focus on how you live, optimizing room sizes, storage solutions, and natural light, to make your Ontario ADU practical and enjoyable for everyday life.

ADU Building Permits

Navigating the permitting process in Ontario is straightforward with our ADU Building Permit Services. We prepare complete applications, handle plan check responses, and track approvals so that your project stays on schedule.

This includes utility coordination, Title 24 compliance, structural checks, and any revisions required by the city for smooth permitting.

Permitting Unpermitted ADUs

If your existing space lacks proper approvals, our Permitting Unpermitted ADUs Services can help legalize it.

We document current conditions, produce as-built drawings, and develop a compliance plan. Our trusted contractor partners can complete upgrades needed for a successful final inspection.

ADU Construction

We hand off precise, builder-ready plans to our vetted construction partners and provide ongoing field coordination.

From foundation to finishes, our ADU Construction Services make sure your Ontario project is built efficiently and to the highest standard.

Spanish-Style ADUs

Our Spanish-style ADU designs feature stucco exteriors, clay tile roofs, arched openings, and wrought-iron details, blending seamlessly with historic Spanish Revival architecture found in many Ontario neighborhoods.

We fine-tune proportions, trim, and landscaping so the ADU looks authentic and complements nearby homes.

Studio ADUs

For smaller footprints, our studio ADUs maximize functionality with Murphy beds, built-in storage, and efficient kitchens.

We carefully position windows to balance daylight and privacy, making even compact spaces feel open, airy, and comfortable.

Cottage ADUs

Our cottage ADUs feature charming gables, lap siding, and inviting porches that enhance Ontario's traditional neighborhoods.

Inside, flexible room layouts create cozy, livable spaces for guests or long-term tenants.

2 Bedroom ADUs

Our 2 bedroom ADUs offer versatility for families or rental purposes. We design efficient closets, baths, and laundry areas to ensure smooth circulation and a spacious feel.

This option is ideal for multi-generational living or higher-demand rental units in Ontario.

3 Bedroom ADUs

For larger households or investment purposes, our 3 bedroom ADUs provide ample space while staying on budget.

We refine structural planning and energy compliance measures so bigger units are practical, comfortable, and cost-effective.

Garage ADUs

A garage conversion ADU is a smart, cost-efficient solution that adds valuable living space without impacting your property's footprint. We assess structure, clearance, and utilities early to simplify permitting and avoid surprises during construction.

Junior ADUs

A JADU carved from existing space can be a quick route to rental income or aging-in-place solutions. We ensure compliance with fire separation, egress, and kitchenette requirements while controlling costs.

Why Ontario Homeowners Choose LADU

We understand Ontario's unique residential landscape, offering ADU solutions that:

• Match neighborhood architectural styles.
• Comply with local building codes.
• Maximize lot potential.
• Generate potential rental income.
• Support flexible living arrangements.

Ontario homeowners partner with LADU because our architect-led method simplifies every decision, from selecting a unit type to right-sizing the accessory dwelling unit for your lot and zone.

We navigate state mandates for single-family parcels, align plans with city standards, and tailor designs that help you generate rental income while maintaining curb appeal.

For many homeowners, ADUs provide essential living space for relatives while offering long-term rental potential that supports household finances. We also help ensure that ADUs advance affordable housing goals without compromising comfort, privacy, or quality.

Book Your Free ADU Site Visit

Ready to explore ADU possibilities for your Ontario property? Contact LADU today for a comprehensive, no-obligation site consultation and fixed-fee design proposal.

Our Ontario ADU specialists will walk your site; review setbacks, utilities, and potential floor layouts; and advise on the best accessory dwelling unit type for your goals. We'll discuss cost ranges, contractor selection, and a realistic schedule so you can plan confidently.

If you're early in planning, we'll also cover rental considerations, how ADUs support affordable housing objectives, and how to future-proof your living space with flexible layouts. Our approach provides everything you need to start building an ADU in Ontario with clarity.

Call (213) 855-3334 to learn more, or schedule your free site evaluation today.