Solid ADU
Attached ADU done right in Westchester
Looking for a reliable contractor for your attached ADU in Westchester? We match homeowners throughout Westchester and the surrounding neighborhoods with vetted, CSLB-licensed contractors, and we tell you honestly what is realistic for your lot.
- One point of contact from first idea to final inspection
- Built by vetted, CSLB-licensed contractors from our network
- Compare clear fixed proposals before construction starts
No obligation · Response within 24 hours · Your details are only used to contact you.
- [YEARS] years of experience
- [PROJECTS]+ completed projects
- Response within 24 hours
- Free feasibility check
- Vetted, CSLB-licensed contractors
You do not have to look far for an attached ADU in Westchester. We regularly guide projects across Los Angeles, and the contractors in our network plan the build around your schedule. We are also active in Playa del Rey, Del Rey and Venice.
Westchester was built out in the 1940s and 1950s as tract housing for the aerospace workforce, and that heritage shows in its wide, flat lots and orderly streets around Loyola Marymount University. The typical home is a single-story postwar house with an attached or detached two-car garage, both of which can become an ADU: attached garages convert into connected suites, detached ones into fully independent units. Demand for those units is steady, from LMU students and staff to people working at LAX and the Silicon Beach offices in Playa Vista. The generous lot sizes also leave room for detached new-build ADUs when owners want to keep their garage. Westchester's level terrain and consistent construction make it one of the most predictable places on the Westside to build. Think of 1940s aerospace-era tract homes, postwar ranch homes, single-story mid-century houses and expanded family homes: we tailor the approach to the type of home and the condition of your lot and existing structures.
An attached ADU (Accessory Dwelling Unit) is a complete, self-contained home that shares at least one wall with your main house. It has its own entrance, kitchen, bathroom and living space, so it can be rented out or used by family while everyone keeps their privacy. You can build it as a new addition on the side or rear of your house, or convert an existing part of your home, such as a rear wing or an oversized family room, into a separate unit.
Every property is different. That is why we always start with a free conversation about your lot, your goals and your budget range. You do not need to know exactly what you want yet: during that conversation we go over the options, the approach and the cost factors.
Want to know what is possible on your Westchester lot?
Call now or leave your phone number. We walk through your situation for free, with no obligation.
Attached ADU in Westchester: what is possible
Free feasibility check
We review your lot, existing structure, setbacks and utility locations, and tell you what size and layout of attached ADU is realistic before you spend anything on design.
Design and floor plans
We help you shape the unit around how it will be used: rental, family housing or home office with living space. You review the layout and finishes before anything moves toward permitting.
LADBS plan check and permits
Your contractor's team prepares the full plan set with structural, Title 24 energy and site documents and submits it to LADBS plan check. We guide you through the process, track corrections and keep the application moving through to permit issuance.
Connecting to the existing structure
An addition has to carry its own loads and tie cleanly into your house. Your contractor handles the foundation, framing and roof connection so the new unit and the existing structure work together, verified by inspection.
Converting part of your home
Instead of building new, your contractor can turn an existing section of the house into the ADU: closing interior openings, adding the separate entrance and upgrading the space to full dwelling standards.
Private entrance
Every ADU needs its own exterior entrance. The plans place it for privacy on both sides, with its own path, address marking and lighting, so tenants never walk through your space.
Fire and sound separation
The wall and any floor or ceiling between the units are built as rated assemblies: layers of fire-resistant drywall, insulation and sealed penetrations that slow fire spread and block everyday noise.
Plumbing, electrical and HVAC
Your contractor runs new supply, drain and electrical lines, adds or extends panels where needed, and installs efficient heating and cooling, typically a ductless mini-split, sized for the unit.
Kitchen and bathroom build-out
A full kitchen and bathroom are what make it a dwelling. Your contractor builds both complete: cabinets, counters, appliances, fixtures, waterproofing and tile.
You can find the full overview on our attached ADU page.
Why invest in an attached ADU?
Most homeowners we talk to want the extra space or rental income but get stuck on the same points. Recognize any of these?
- You are not sure whether your lot even qualifies for an attached ADU, or how big it could be.
- You need rental income or space for family, but a detached backyard unit does not fit your lot.
- The permit process feels like a black box: plan check, corrections, inspections, all with their own rules.
- You have talked to an architect and a contractor separately and got two stories that do not line up.
- You do not know how to vet a contractor, or which quote you can actually trust.
- You worry the addition will look bolted on and hurt the value of your home.
What happens after you reach out
- 1
Free feasibility check
Call us or leave your number, and we respond within 24 hours. We look at your lot, your garage or backyard, and your utilities, and we talk through what you want: rental income, space for family, or a home office. You get an honest picture of what is possible before you spend anything.
- 2
Matched with the right contractor
We match you with vetted, CSLB-licensed contractors from our network whose track record fits your type of ADU, your lot and your budget. We verify licenses, insurance and past work, so you do not have to.
- 3
Compare clear fixed proposals
You receive clear fixed proposals with the scope, schedule and price spelled out. No fine print and no surprise costs. You compare, ask us anything, and pick the contractor you feel confident with, at your own pace.
- 4
Plans and LADBS permits
Your contractor's team prepares the complete permit set: architectural plans, structural calculations and the energy compliance documents California requires. We guide you through the LADBS permit process and keep you posted on plan check and corrections. Nothing is submitted until you approve the design.
- 5
Your contractor builds, we stay involved
Your licensed contractor builds your ADU and schedules every required city inspection along the way. We stay involved as your single point of contact, so you always know where things stand.
Attached ADU costs in Westchester
What an attached ADU costs depends heavily on the route you take. Converting an existing part of the house that already has a roof and slab is a different project from building a new addition with its own foundation. That is why you will not find standard prices here: for your situation they would almost always be too high or too low.
- New addition or conversion of existing space
- The size and layout of the unit (studio, one or two bedrooms)
- Foundation and structural work needed to tie into the existing house
- The condition of the existing structure, slab and roof at the connection point
- How far water, sewer and electrical lines must be extended, and whether the panel needs upgrading
- The fire and sound separation assemblies between the two units
- Kitchen and bathroom scope and the finish level you choose
- Matching the exterior: stucco, siding, roofing and windows
Get a free feasibility check for your project
Leave your phone number and we will call you back within 24 hours.
A project nearby: Mar Vista
A licensed contractor from our network completed this project in Mar Vista, in the same part of Los Angeles as Westchester.
Want a similar result on your property?
Talk your project through with us. Free, and with no strings attached.
Also serving the area around Westchester
We also guide attached ADU projects in Playa del Rey, Del Rey, Venice and the rest of Westside.
Frequently asked questions about attached ADU in Westchester
Do you also work in the area around Westchester?
Absolutely, including in Playa del Rey, Del Rey and Venice. Take a look at our service areas page for every neighborhood we cover.
What does an attached ADU cost in Westchester?
That depends on factors such as the size of the project, the condition of the existing structure and the finishes you choose. That is why there are no standard prices. Leave your phone number and you will receive a free feasibility check, followed by a detailed fixed proposal from a vetted licensed contractor.
Do I need to know exactly what I want?
No. You do not need to have chosen a layout, materials or finishes yet. During a free consultation we walk through the options and help you decide what fits your property and your goals.
What happens after I leave my details?
We call you back within 24 hours to briefly go over your plans. After that, if you want, we run your free feasibility check and set up a site visit with a vetted contractor from our network.
Do you visit the property first in Westchester?
Yes. For most projects the licensed contractor we match you with starts with a free site visit at your property in Westchester. That way your lot and the existing structure are properly assessed, and the proposal you receive is realistic.
How soon can you start in Westchester?
That depends on your contractor's schedule, the size of your project and the LADBS plan review, which we guide you through. After your request we contact you within 24 hours and map out a realistic timeline right away.
Ready for your attached ADU in Westchester?
Call now or leave your name and phone number. We discuss your project with no obligation and you hear from us within 24 hours.
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