Detached ADUs, attached units, and garage conversions across Ventura County, Santa Barbara, and greater Los Angeles. An ADU is a complete small building — structure, power, and roof — and NRG Construction self-performs all three of those trades. The entire shell of your unit is built by our own crews, under our own CSLB licenses, with one company accountable from feasibility to final inspection.
"An ADU is a whole small building — structure, power, and roof. Those are exactly the three trades we never sub out."
Every lot and every family points to a different answer. The right one depends on your setbacks, your utilities, your existing structures, and how you plan to use the unit — which is exactly where we start.
A stand-alone building in the yard — new foundation, new framing, its own roof, and full utility connections. The most flexibility in layout and privacy, sited wherever your setbacks and lot coverage allow.
A unit built onto the existing house. The work that decides whether it succeeds — structural tie-ins, matched rooflines, and coordinated electrical — happens in the trades we self-perform, not in a sub's schedule.
Your existing slab and shell put to work. Conversions turn on the details — fire separation, insulation, egress windows, and almost always electrical upgrades — and we scope all of it honestly before you commit.
From sill plate to ridge, the structure of your ADU is framed by NRG crews. On conversions and attached units, that's the difference between clean tie-ins and a sub improvising against your existing house.
ADUs live or die on power. Our own C-10 division evaluates your panel, runs the feeder, and wires every circuit in the unit — and if the service needs an upgrade, the same company handles that too.
New roof on a detached unit or a tie-in that has to disappear into your existing roofline — NRG Roofing, our dedicated roofing division, gets it weathertight on our schedule.
On a small building, one late sub can stall the whole job. When the structure, the wiring, and the roof all belong to the same company, the schedule has one owner — and so does every question you'll ever have about the work.
The most expensive ADU mistake is designing a unit the lot can't support. Before design money gets spent, we look at the three things that decide what you can actually build.
Where a unit can legally sit: yard setbacks, lot coverage, easements, and separation from the main house. For conversions, whether the existing footprint carries the day. This is what makes or breaks a floor plan.
Sewer and water routing, and — the one most homeowners miss — whether your electrical panel can carry a second dwelling. Our C-10 electricians answer that from the panel itself, not from a guess.
Slope, drainage, existing hardscape, and how crews, concrete, and lumber actually get to the back of your lot. Site conditions shape the work — better to know on day one than in a change order.
We walk the property, check setbacks, utilities, panel capacity, and site access, and give you a straight answer on what your lot supports — detached, attached, or conversion — before anyone spends design money.
We work alongside your designer or architect, reviewing the plans for buildability as they take shape. Once the set is approved, we price it with measured quantity takeoffs — a firm written proposal with inclusions and exclusions spelled out.
Foundation through final inspection. Our crews self-perform the framing, electrical, and roofing, we manage everything else, and you get clean documentation the whole way to handover.
They're different projects. A conversion puts your existing slab and shell to work, which usually means less new construction — but it brings its own scope: fire separation, insulation, egress, and almost always electrical work, plus you lose the garage. A detached unit is a clean slate with more new construction and more freedom in layout and privacy. The honest answer comes from a feasibility visit — your setbacks, your panel, and your existing structure decide most of it.
Size and layout, foundation and site conditions, how far utilities have to travel, whether your electrical service needs an upgrade, and the level of finish you choose. Detached units carry more new construction than conversions, but conversions carry upgrade scope of their own. We don't price from square-foot averages — your proposal is built from measured quantity takeoffs of your actual plans, so the number reflects your project, not a typical one.
Sometimes yes, often not without work — a second dwelling adds real load, and many older homes are already near capacity. Because NRG holds its own C-10 electrical license, our electricians evaluate your panel during feasibility and, if a subpanel or service upgrade is needed, our own crews perform it. No separate electrical contractor to find, schedule, or coordinate.
It genuinely depends — on the design phase, on your city's plan review, and on the scope of the unit, and we won't pretend otherwise. What we can commit to: a construction schedule in your written proposal, and crews we control on the trades that drive it. Because the framing, electrical, and roofing are our own people, the build doesn't sit waiting on three subcontractors' other jobs.
With a conversation. Call or send the inquiry form with your address and what you're picturing, and we'll talk feasibility — what your lot supports and what the realistic paths are. If you already have plans, we'll price them with a real takeoff. If you don't, we work alongside the designer or architect you choose, reviewing for buildability from the first sketch.
Tell us about your lot and what you're picturing — a detached unit, an attached addition, or a garage conversion — and get a straight answer on what it takes. No pressure, no obligation.
Tell us about your property and what you're picturing — a detached unit, an attached addition, or a garage conversion — and we'll reach out to talk feasibility and next steps.
We typically respond within one business day.