Who's Actually Building Your ADU?

When you hire a general contractor, you’re not hiring one person — you’re hiring everyone they bring onto your property. The foundation crew, the framers, the electrician, the plumber, the finish carpenters. Two contractors can hand you nearly identical bids and deliver very different projects, because the real difference isn’t on the paper. It’s in who shows up.

Most homeowners comparing builders focus on price, timeline, and the portfolio. Those matter. But there’s a question that tells you more about how your project will actually go than almost any other: who will be doing the work, and how long have you worked with them?

Every builder relies on subcontractors — the question is which ones

First, some reassurance: subcontractors are not a red flag. They’re how residential construction works, and how it’s supposed to work. Foundation and concrete, framing, roofing, electrical, plumbing, HVAC, drywall — these are specialized, individually licensed trades. A concrete crew that pours foundations every week will do better work than a generalist who pours a few a year, and California licenses these trades separately for good reason.

So the question to ask a builder isn’t “do you use subcontractors?” The answer is almost always yes. The questions that matter are which subcontractors, how they were chosen, and how long the builder has worked with them — because that’s where projects quietly succeed or struggle.

Two ways a contractor can staff your project

Behind the scenes, general contractors staff projects in one of two basic ways:

• Long-term trade partners. The builder works with the same framing crew, the same concrete sub, the same electrician across many projects and many years. Everyone knows the builder’s standards, how their jobs run, and each other.
• Job-by-job bidding. The builder shops each phase of the project out to whichever crew is available and priced right at that moment — sometimes through online platforms built for exactly this. Each trade is a separate transaction.

Neither approach is against the rules, and bidding each phase out can sometimes shave a line item. But it’s worth understanding what you inherit as the homeowner when the team assembling your home has never worked together before:

• Coordination lives at the seams. Most construction problems happen where one trade’s work meets another’s — the framer and the plumber, the concrete crew and the framer. Crews that work together regularly already know how to hand off. Crews meeting for the first time are figuring that out on your project.
• Standards have to be re-explained. A builder’s quality bar is enforced trade by trade, detail by detail. With longtime crews it’s already understood. With a new crew, it depends on how closely someone is checking.
• Accountability is easier to diffuse. When something needs to be made right — during the build or a year later — a sub who values a long relationship with the builder shows up. A crew that took one job at a fixed price has less reason to.

Why repeat crews matter more on a one-off project

An ADU or a custom home isn’t a repeatable product rolling off a line. It’s a one-off building shaped by your lot, your soil, your existing house, and your city’s inspectors. Tight backyard access, a sloped site, an older main house with undersized utilities — every project has its own version of these, and they’re exactly the conditions where experienced, coordinated crews earn their keep.

A framing crew that has done dozens of projects with the same builder doesn’t need to learn how that builder sequences a job, handles an inspection, or wants a tricky detail solved. They’ve done it. That experience doesn’t show up as a line on a bid — it shows up as a schedule that holds, inspections that pass the first time, and problems caught while they’re still cheap to fix.

It matters again years later. Homes get lived in, and occasionally something needs attention after the final invoice is long paid. Whether that call gets returned — and who shows up to fix it — usually comes down to relationships that were built over many projects, not one.

You have the right to ask — and now it’s in the contract

California recently strengthened homeowners’ right to know who’s working on their property. Under Senate Bill 517, effective in 2026, home improvement contracts must state up front whether subcontractors will be used — and when they are, you’re entitled to request a list of them, including each sub’s name, contact information, license number, and license classification.

A builder with nothing to hide answers these questions happily, law or no law. When you’re comparing builders, ask:

• How long have you worked with your framing and concrete crews? Listen for specific names and history, not vague assurances.
• Who supervises the trades day to day? You want a builder whose own project lead is on site regularly — not one who hands your project off between crews.
• Will the crews on my project have worked together before?
• Who do I call if something needs attention a year after completion? The confidence of the answer tells you a lot.

Vagueness on any of these — a builder who can’t name their subs, or won’t say who’s running the site — tells you something too. We’ve written more about vetting builders in How to Choose an ADU Builder in the Bay Area.

How Burton Builders works

We’ll be direct about where we stand, because it’s the way we’ve always built. Burton Builders has completed hundreds of projects across the Bay Area — ADUs, custom homes, remodels, and multifamily work — and the crews behind them have been remarkably consistent.

The framing, concrete, and finish trades on our projects are crews we’ve worked with for years, project after project. They know our standards, how our jobs run, and each other — and our own project lead supervises the site day to day, so there’s never a question about who’s accountable for what happens on your property.

That consistency is why our projects run the way they do — from first idea to final inspection, the people on site have done it together many times before, on lots and homes like yours.

The bottom line

An ADU or custom home can be assembled from parts by whoever’s available, or built by a team that has done it together for years. Both can look the same in a bid. They rarely feel the same during construction — and the difference tends to show up at the seams, on the schedule, and years down the road when you need someone to pick up the phone.

Before you sign with any builder, ask who’s actually building. It’s your property, your money, and — under California law — your right to know.

Planning an ADU or custom home in the Bay Area?

We’re happy to talk through your project — and to tell you exactly who would be building it. Burton Builders works across the Bay Area and takes on select projects in the Sacramento area.

Start a conversation about your project.