Home Additions & ADU in Lakewood, CA | Barrett & Sons Construction - Barrett & Sons Construction

Home Additions & ADU in Lakewood - One Fixed Price, Permits Handled

We handle the design, the engineering, and the city permit, then build it. One contract, one crew, one accountable point of contact. Free feasibility check on your lot before you commit.

Call to schedule your free estimate

953+
Cities Served
Free
Written Quotes
Licensed & Insured Written Quotes Free Estimates All Brands Satisfaction Guarantee
Every visit starts with

Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled

Your dream remodel for as low as $199/month*on approved credit; ask for current terms
Styles & brands we work with

Kitchen remodeling
Kitchen remodeling
Bathroom remodeling
Bathroom remodeling
Home additions & ADU
Home additions & ADU
Roofing
Roofing
Windows & doors
Windows & doors
Driveway & pavers
Driveway & pavers
Fence
Fence

Before & after – our own jobs

Before - Recent ProjectBeforeAfter - Recent ProjectAfter
Recent Project
Before - Full RestorationBeforeAfter - Full RestorationAfter
Full Restoration
Before - Complete UpgradeBeforeAfter - Complete UpgradeAfter
Complete Upgrade

Fast, Reliable Home Additions & ADU Across Lakewood

A home addition or ADU in Lakewood typically runs $45,000 to $130,000, depending on whether you’re adding a single room, going up with a second story, or building a detached unit from scratch. That’s the range we quote most often for this city’s 950-to-1,100-square-foot tract homes, nearly all of them built between 1950 and 1954. The real question isn’t just the price. It’s whether the contractor knows what’s behind those 70-year-old stucco walls before the framing crew shows up. We do. Call (877) 610-1318 for a free estimate, and we’ll walk your lot and your plans with you.

Call (877) 610-1318

Why Barrett & Sons Construction Is Lakewood’s Preferred Home Additions & ADU Company

Tom Barrett started this company in 1998, and his sons run the crews today. That’s not a slogan. When you call Home Additions & ADU with Barrett & Sons, you’re talking to the family that signs the change orders and shows up on the job site. We serve Lakewood directly, and because this city’s housing stock is so uniform, we know what we’re going to find before we open the first wall. A 60-amp electrical panel. Galvanized supply lines that belong in a museum. Orangeburg sewer laterals that have been quietly collapsing since the Clinton administration.

That local knowledge matters more than most people realize. A national outfit sends out a project manager who’s never seen a 1952 Lakewood tract house. We’ve seen hundreds of them. Our crews work in the 90712, 90713, and 90714 ZIP codes weekly, and our design team knows which additions trigger which city inspections. Every scope, every allowance, every price change arrives as a written change order before work happens. No surprise invoices. No “the allowance ran out” conversations at the end of the job. And every project is backed by the 90-Day Done Right Promise, written on the contract, not buried in fine print. If it’s not done right, Tom comes back and makes it right. One call.

Our Home Additions & ADU Services in Lakewood

Most Lakewood homeowners come to us with one of four needs. Here’s how we approach each one in this city’s specific housing stock.

ADU Site Prep & Utilities

Before we design anything, we scope the sewer lateral. That’s non-negotiable in Lakewood. The original Orangeburg pipe under most of these homes degrades into a collapsed, egg-shaped mess after 50 to 70 years, which means almost every lateral in this city is either failing or about to. On a garage conversion in the 90713 ZIP, our crew hit a collapsed Orangeburg lateral during site prep. Because we pre-scoped it as step one, we replaced it with PVC, upgraded the 60-amp panel to 200-amp, and the inspector signed off the same week. The conversion stayed on the original draw schedule. That’s what planning looks like.

ADU Site Prep & Utilities

Garage Conversion ADU

Garage conversions are the most popular ADU type in Lakewood for a simple reason: these homes already have attached garages, and the slab is typically in fair shape. But a 1953 garage slab isn’t a finished floor. We usually pour a new slab with sealed joints over the original, because salt-laden soil moisture will wick up through unsealed concrete and destroy whatever flooring you put down. A garage conversion ADU in Lakewood typically runs $30,000 to $80,000, including the new electrical subpanel, insulation, drywall, and the sewer lateral work that almost always comes up.

Garage Conversion ADU

New Detached ADU

A new detached ADU gives you a clean slate, but the ground it sits on is the problem. Lakewood’s soil carries marine salts from the LA Basin, and new slab edges and post bases need hot-dip galvanized hardware or they’ll corrode within five to seven years. We specify stainless or hot-dip fasteners on every exterior connection and seal every paver joint if your ADU has a patio. A detached ADU in Lakewood runs $90,000 to $220,000, and that range reflects the difference between a basic one-bedroom and a two-bedroom with upgraded finishes. You’ll get a written line-item quote either way.

New Detached ADU

Junior ADU & Interior Conversion

Junior ADUs work well in Lakewood’s larger 3-bedroom floor plans, where an existing bedroom and bath can be walled off with a kitchenette and private entrance. The catch is the original electrical service. You can’t run a mini-split, an induction cooktop, and a washer-dryer stack on a 60-amp panel from the Eisenhower era. We factor a panel upgrade into the scope as standard on these jobs. Interior conversions also bring us face-to-face with asbestos-containing floor tiles and attic insulation, which most 1950s Lakewood homes still have. We handle it under permit, the way the inspector wants it handled.

Junior ADU & Interior Conversion
Need help today?Fast, friendly service and a no-obligation free estimate.

Call (877) 610-1318

What happens when you call

  1. 1
    A real person answersNo phone trees - you reach a local pro.
  2. 2
    You get an upfront price rangeHonest numbers before anyone is dispatched.
  3. 3
    A background-checked tech heads outLicensed & insured, dispatched right away.
  4. 4
    You approve before work beginsNothing starts until you say go.

Trusted Brands We Service in Lakewood

We install windows from Simonton and Ply Gem on our Lakewood sunrooms and enclosed patios, and we like PGT’s impact-rated lines for homeowners who want storm protection without the heavy look of aluminum shutters. These aren’t mystery brands off the back of a van. You can look them up. When we order a Simonton double-hung for a 1954 tract house, we check the wall depth and the existing flashing first, because Lakewood’s stucco hides more surprises than most cities. Our suppliers keep these brands stocked for us, and we keep turnarounds tight for our neighbors in the 90711 and 90712 ZIP codes.

Common Home Additions & ADU Problems We See in Lakewood Homes

  • Original galvanized supply lines. These are corroding from the inside out in nearly every 1950s Lakewood home. You won’t know until we cut into a wall and the pipes look like a clogged artery. We plan for replacement in every addition scope.
  • 60-amp electrical panels. A second story or ADU will overload the original panel. We spec a 200-amp upgrade as part of every major addition, and the city requires the inspection. It’s cheaper to do it during the addition than after.
  • Unsealed paver joints and slab edges. Lakewood sits about 10 miles inland, close enough to the Pacific that salt-laden moisture moves through the soil. Unsealed paver patios heave and crack within three winters. We seal every joint and spec marine-grade finishes where it counts.
  • Standard interior-grade window frames on sunrooms. Sunrooms and enclosed patio additions in Lakewood need marine-grade or impact-rated frames. Standard frames rot and warp from marine moisture, then leak air and grow mold. The coastal spec costs more up front. It’s cheaper than replacing the windows in six years.

Pricing for Home Additions & ADU in Lakewood, CA

Here’s the straight answer on what this work costs in Lakewood, and why the coastal-spec version costs more than the inland number you’ll see on a generic bid from a contractor who doesn’t work here.

Project Type Typical Lakewood Range
Home Addition $45,000 - $130,000
ADU Construction $90,000 - $220,000
Garage Conversion $30,000 - $80,000
Countertop Installation (marine-grade sealant upcharge) $2,000 - $6,500

The gap between a coastal-spec and an inland-spec addition is real, and it’s mostly hardware and sealing. Hot-dip galvanized post bases instead of standard steel. Stainless fasteners instead of bright nails. Sealed paver joints instead of open sand joints. Marine-grade window frames instead of standard interior frames. You’ll pay maybe 8 to 15 percent more up front for the coastal spec. The inland spec fails in five to seven years and you pay for it twice. If you ever get a bid that doesn’t mention this, ask the contractor how many Lakewood homes they’ve worked on. Then call (877) 610-1318 for a free estimate from someone who has.

We Also Serve Cities Near Lakewood

Barrett & Sons Construction serves Lakewood and the surrounding communities, including Signal Hill, Bellflower, Long Beach, and Paramount. If you’re in any of those cities and want a contractor who knows this strip of the LA Basin’s 1950s tract housing, call us. We’ll bring the same written-scope, permit-pulled approach to your job that we bring to every Lakewood addition.

Serving Lakewood, CA - Our Local Coverage Area

We’re based in the Lakewood area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.

FAQs - Home Additions & ADU in Lakewood

Get Your Free Estimate for a Home Addition or ADU in Lakewood

If you’re weighing an addition, a second story, or an ADU on your Lakewood lot, call Barrett & Sons Construction at (877) 610-1318. We’ll walk your property, scope the sewer lateral, check your panel and your pipes, and give you a written line-item estimate with no trip charge inside the county. Tom Barrett publishes his name, his address, and his license number. Look it up before you sign anything. Then call the number and talk to a live person, 24/7. That person will be us.

Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Lakewood and the surrounding LA Basin communities.

Why Los Angeles Chooses Barrett & Sons Construction

We set the standard for construction in Los Angeles.

No Change-Order Surprises

The written quote you sign is the price you pay. Anything we find mid-job gets priced and approved by you in writing before we touch it.

Licensed & Insured

Fully certified technicians who meet all local and state licensing requirements.

Upfront Pricing

No hidden fees, no surprises. You approve the price before any work begins.

Guaranteed Work

Every repair and installation is backed by our workmanship warranty and satisfaction guarantee.

How It Works in Los Angeles

Getting your construction handled is simple and fast.

1

Call or Request a Free Estimate

Tell us about your construction needs and we provide an upfront, transparent quote - no obligation, no hidden fees.

2

Licensed Technician Dispatched

A background-checked, certified technician arrives in Los Angeles - typically within 30-60 minutes, with parts stocked on the truck.

3

Problem Solved, Guaranteed

We complete the job to your full satisfaction, backed by our warranty and 100% satisfaction guarantee.

What happens when you call

  1. 1
    A real person answersNo phone trees - talk to a local construction pro.
  2. 2
    You get an upfront price rangeHonest numbers before anyone is dispatched. No surprises.
  3. 3
    We come out and measureLicensed & insured, at a time that suits you - the visit and the quote are both free.
  4. 4
    You get the price in writingLine-itemed, yours to keep, and nothing starts until you say go.

What Los Angeles Customers Say

Trusted by homeowners across Los Angeles and surrounding areas.

★★★★★

"His sons run the crews and they were in our house for four months. Not once did I feel I had to be home to keep an eye on things."

Camila Fuentes · Verified customer
★★★★★

"Beautiful work and honest pricing throughout. The project ran about three weeks past the estimate waiting on the cabinets, which was the supplier rather than him, though the delay was still real."

Genevieve Ashcombe · Verified customer
★★★★★

"Full kitchen down to the studs. He found the previous owner had done the wiring himself and it was genuinely dangerous, showed me, and put it right properly rather than boxing it back in."

Augustus Nwachukwu · Verified customer

Current Offers

Bring these savings to your next appointment.

Free On-Site Estimate & Written Quote

No obligation. We measure, price the job in writing, and the quote is yours to keep.

Expires Dec 31, 2026
$40

$40 Off Any Repair Over $200

Expires Dec 31, 2026
Free

Free Second Opinion on Any Written Estimate

Expires Dec 31, 2026
Free

No Trip Charge Inside Our Own County

Expires Dec 31, 2026
10%

Senior & Veteran 10% - Always

Expires Dec 31, 2026

Ready for Construction in Los Angeles?

Call now for a free estimate - or request one below. Licensed, insured, and here with fast after-hours help in Los Angeles.

(877) 610-1318

Request a Free Estimate in Los Angeles

Tell us about your construction needs - we'll respond within the hour.

By requesting your free estimate, you accept our Privacy Policy and consent to receive communications through phone, text, or email regarding your service needs, including from the affiliated professionals who may take on the job.

Prefer to text? Text Us
Areas We Serve
Call Now - 24/7 Dispatch