Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
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After
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AfterFast, Reliable Home Additions & ADU Across Pacifica
A home addition or ADU in Pacifica typically costs $45,000 to $130,000 for a room addition, and $90,000 to $220,000 for a new detached ADU. The number moves around based on hillside engineering, coastal zone permitting, and what your lot can actually handle. If you live anywhere between the bluffs and the ridge, you already know Pacifica builds differently than the flat cities over the hill. Call us at (877) 610-1318 and we’ll walk the property with you before you commit to anything.
We’ve been in and out of Pacifica homes for over 29 years now, and we know what the marine layer does to framing, what Coastal Commission review does to a timeline, and what fog-wet soil does to a foundation plan. That local knowledge saves you money before you sign, not after. Tom Barrett signs every contract, his sons run the crews, and every quote comes in writing before any work starts.
Why Barrett & Sons Construction Is Pacifica’s Preferred Home Additions & ADU Company
We’re not a franchise. Tom Barrett founded this company in 1998, and his sons are on-site most days in Pacifica, not checking in from a regional office. When you call, a live person answers. When you have a question about your addition or ADU three weeks into the build, you talk to someone who was standing in your kitchen that morning.
Pacifica homeowners have a particular reason to be picky about who they hire. The last contractor many of them used told them permits were optional, then vanished when the inspector showed up. We publish our license number, our name, and our address. Look it up before you sign anything. We pull permits on every eligible job in Pacifica, and the inspection sign-off is part of the contract, not a favor we do you.
Our customers in Linda Mar, Sharp Park, and Fairway Park keep our calendar full because we do what we say we’ll do. Every change order arrives in writing before work proceeds. Every allowance is on paper. Nothing shows up as a surprise invoice at the end. And every job carries our 90-Day Done Right Promise: if it’s not done right, Tom comes back and makes it right, one call.
Our Home Additions & ADU Services in Pacifica
ADU Design & Permitting
Most Pacifica ADU projects start with a Coastal Development Permit, and many require a geotechnical report before the city will even look at your drawings. We coordinate both from day one. If your property sits within a few blocks of the bluff, expect the Coastal Commission timeline to be part of your bid, not an excuse you hear about in month three. We design the unit, handle the paperwork, and build it.
Garage Conversion ADU
Converting an existing garage in Pacifica routinely lands between $30,000 and $80,000. That’s the most affordable path to a legal rental unit on your lot, and it keeps the footprint where it already is, which matters on hillside parcels. Older Pacifica garages from the 1950s and 1960s often need framing upgrades and new foundations before the conversion can pass inspection. We check that before we quote, so your first number is your real number.
New Detached ADU
A new detached ADU in Pacifica runs $90,000 to $220,000. The spread depends on whether you’re on flat ground in Fairway Park or cutting into a slope above Sharp Park. Detached units trigger the full Coastal Commission review when you’re in the coastal zone, which covers most of Pacifica’s developed footprint. We build that permitting timeline into the schedule from the first meeting, so you know when shovels actually hit dirt.
Junior ADU & Interior Conversion
A junior ADU or interior conversion inside the existing envelope of your Pacifica home is often the fastest and least expensive way to add a legal living unit. You’re not expanding the footprint, which simplifies both planning review and the geotechnical questions that come with new foundations on coastal hillsides. We build these often for homeowners who want rental income without the full detached-unit process.
Beyond ADUs, our Home Additions & ADU team also handles second-story additions, sunrooms, and enclosed patio conversions. A lot of Pacifica families also roll in Kitchen Remodeling in Pacifica or Bathroom Remodeling in Pacifica as part of the same addition, which saves on mobilization and lets us sequence the work without tearing the house apart twice.
What happens when you call
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A real person answersNo phone trees - you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Pacifica
We don’t put mystery materials on your Pacifica job. We install products you can look up, from manufacturers that stand behind their stuff. On Pacifica hardscape and exterior work we regularly use Techo-Bloc and Cambridge Pavers, which hold up against salt air better than generic concrete. For interior builds, we use named brands across every trade. When we stock parts for Pacifica customers, we keep them local to our San Francisco Bay Area operation, so there’s no week-long wait for the right hardware.
Common Home Additions & ADU Problems We See in Pacifica Homes
- Coastal zone permits catching owners off guard. Most of Pacifica sits inside the coastal zone, which means a Coastal Development Permit is often required. National companies over the hill don’t know this until it’s too late. We build it into every proposal from day one, because the permit inspector here works for you, not us, and that’s how we like it.
- Salt-fog framing and fastener corrosion. Decades of marine air mean original wood framing and metal connectors on Pacifica homes are often corroded or moisture-damaged in ways you can’t see until walls open. We spec stainless or hot-dipped galvanized hardware as a baseline, not an upgrade.
- Hillside soil stability surprises. Lots in Sharp Park and across the hillsides slope enough that drainage and soil stability affect foundation design. A flatland contractor from Daly City or Millbrae might not flag it. We do, before we quote, so the foundation doesn’t turn into a change order later.
- Fog-driven moisture trapping in wall cavities. Pacifica’s near-daily marine layer keeps humidity high year-round. Poor vapor management leads to rot and mold inside addition walls. We treat water management as a structural requirement here, not a checkbox.
Pricing for Home Additions & ADU in Pacifica, CA
As we’ve said, a room addition in Pacifica lands between $45,000 and $130,000, a garage conversion between $30,000 and $80,000, and a new detached ADU between $90,000 and $220,000. The biggest cost drivers here are hillside engineering, coastal permitting, and foundation work. Flat-lot additions on stable ground sit at the lower end. Slope work and geotechnical reviews push toward the top. When you call, we’ll give you a written, line-item estimate that includes permits, materials, labor, and the timeline. No change orders unless you change the scope and sign a change order first. Call (877) 610-1318 to schedule your free estimate in Pacifica.
We Also Serve Cities Near Pacifica
If you’re in San Bruno, South San Francisco, Millbrae, or Daly City, we serve those communities too. Many of our Pacifica customers have family or rental properties over the hill, and we’re glad to handle those jobs. We also work throughout the broader Pacifica area, including all of ZIP code 94044.
Serving Pacifica, CA - Our Local Coverage Area
We’re based in the Pacifica 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 Pacifica
Most Pacifica projects start within 2 to 4 weeks of contract signing for design and site work, but permits through the city and Coastal Commission can add months. We give you a written timeline at the first meeting and update it in writing as milestones move. Call (877) 610-1318 and we’ll give you a realistic start date for your specific lot.
Yes, we work throughout Pacifica, including Linda Mar, Sharp Park, Fairway Park, and every hillside street in 94044. We drive our own crews there, not subcontracted labor from outside the area.
If your Pacifica property is within the coastal zone, which covers nearly all of the city’s developed footprint, expect a Coastal Development Permit and often a geotechnical report before construction. That can add months and thousands of dollars. We factor it into your timeline and price from the first proposal, so it doesn’t blindside you later. Call (877) 610-1318 for an exact quote on your property.
In Pacifica specifically, our home addition pricing lands between $45,000 and $130,000 and ADU construction between $90,000 and $220,000. Contractors from over the hill often underbid, then discover coastal permits and hillside engineering after the contract is signed. Our first number includes those costs. A written estimate is free, so call (877) 610-1318 and compare line by line.
The 90-Day Done Right Promise is written on every Barrett & Sons contract, including every job in Pacifica. If anything isn’t done right within 90 days of completion, Tom Barrett comes back and makes it right, one call. It’s not fine print. It’s the same guarantee he’s honored since 1998.
Call Barrett & Sons Construction at (877) 610-1318 to schedule your free estimate for a home addition or ADU in Pacifica. We answer the phone, we show up, and every price arrives in writing before a single nail moves.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Pacifica and surrounding Bay Area communities since 1998.