Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
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AfterFast, Reliable Home Additions & ADU Across Plano
A room addition or ADU in Plano typically runs $45,000-$130,000 for a standard addition, while a detached ADU usually falls between $90,000 and $220,000 depending on size, utilities, and finishes. Those are honest numbers for this market, not phone quotes that shift once someone walks your property. If you’re weighing a garage conversion, a second story, or a backyard ADU in Plano, the smartest first move is a written, line-item estimate from a contractor who works in your ZIP code regularly. Call (877) 610-1318 and we’ll schedule a free walkthrough.
Plano isn’t like other North Texas cities when it comes to construction. The black clay under most of 75074, 75075, and 75086 moves with every drought and rain cycle, and that single fact shapes every footing, slab cut, and foundation tie-in we plan. Our crews work these streets every week, from the 1980s subdivisions near Carpenter Park to the newer builds west of Preston Road, and we know what the city inspector is going to ask before he asks it.
Why Barrett & Sons Construction Is Plano’s Preferred Home Additions & ADU Company
Tom Barrett founded this company in 1998, and his sons run the crews that show up in Plano. That’s not marketing copy. Tom’s name, address, and license number are published, and you can look them up before you sign anything. We encourage it. The last thing a Plano homeowner needs is another out-of-state outfit quoting one number on the phone and handing over a different one at the door.
Homeowners in Plano call us because the permit process here is not optional, and we treat it that way. Every addition we build has permits pulled and inspections signed. Every allowance and every price change arrives as a written change order before work happens. If something isn’t right when the job is done, the 90-Day Done Right Promise is written on the contract, not buried in fine print. One call brings Tom back.
Crew members are background-checked and uniformed. A live person answers the phone 24 hours a day, seven days a week. That matters when you’re coordinating a crew on a quiet cul-de-sac in 75026 and you need a real answer, not a voicemail box.
Our Home Additions & ADU Services in Plano
This is the full scope of what we build in Plano. Each of these gets a dedicated plan, a written scope, and a fixed price before we move a single board.
ADU Design & Permitting
Plano’s post-tension slab construction means design work starts with locating tendons before anyone draws a foundation line. We handle the full permitting path with the City of Plano, including the structural drawings, the site plan, and the inspections. If your lot is in an older subdivision in 75074 where original plans were never filed, we bring in a GPR scanner before any saw cut touches concrete.
Garage Conversion ADU
A garage conversion in Plano generally runs $30,000-$80,000, and it’s often the fastest path to a rentable unit or an in-law suite. The catch in this city is what’s under the slab and what’s running through the walls. Older garages in 75075 frequently lack the sub-slab plumbing needed for a bathroom or kitchenette, which means scoped trenching and careful tendon avoidance before any concrete is opened.
New Detached ADU
A new detached ADU in Plano typically lands between $90,000 and $220,000 depending on square footage, foundation depth, and utility runs. Because of the expansive clay, we engineer footings below the active zone rather than guessing. This is the difference between a building that stays square through three summers and one that starts showing door cracks by year two.
Junior ADU & Interior Conversion
When you have an oversized bedroom suite, a finished attic space, or a bonus room that can legally become a Junior ADU, the budget is usually far lower than building new. The work here is about egress windows, kitchenette plumbing, and separating utilities enough to satisfy Plano code. We walk the space with you, tell you what’s feasible, and put the number on paper before you commit.
If you’re also considering changes inside the main house while we’re on site, we handle Kitchen Remodeling in Plano and Bathroom Remodeling in Plano with the same written-scope, permit-pulled approach.
What happens when you call
- 1
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 Plano
We’re picky about materials because the Plano climate punishes cheap ones. Clay movement, hail seasons, and North Texas sun are hard on a structure. That’s why our additions use GAF roofing, Schluter waterproofing systems, and Grohe plumbing fixtures where the scope calls for them. You can look up every brand we install and verify what you’re paying for. If a sub-contractor suggests a mystery brand off the back of a van, we say no and tell you why.
Common Home Additions & ADU Problems We See in Plano Homes
- Tendon strikes during slab work. In Plano’s 1980s subdivisions, post-tension tendon layout drawings were often never filed or have been lost entirely. Contractors who skip GPR scanning before a core drill or slab saw cut end up severing tendons, cracking slabs, and getting a City of Plano stop-work order.
- Foundation movement on additions. The Blackland Prairie clay under 75026 and 75086 shrinks in drought and swells after spring rain. An addition tied to an existing slab with the wrong footing depth will pull away within a few seasons. We engineer for the soil, not for the rendering.
- Winter Storm Uri repair backlog. February 2021 left thousands of Plano homes with wind, water, and framing damage, and the repair backlog persisted for years in older subdivisions. If your addition project is following storm repair, we sequence the work so you’re not paying twice for the same wall opened up.
- Permit surprises. Some Plano homeowners discover after signing a contract that their previous contractor considered permits optional. The permit inspector works for you, not for the contractor. We pull permits on every eligible job and let the inspector do his job at every stage.
Pricing for Home Additions & ADU in Plano, TX
Here’s what you can expect in this market. A standard room addition in Plano runs $45,000-$130,000. A garage conversion typically lands at $30,000-$80,000. A new detached ADU is $90,000-$220,000 depending on size, foundation work, and utility runs. Those numbers are honest starting points, and the final price depends on square footage, finishes, site access, and what the soil report says about your lot.
What we will not do is quote you one number on the phone and present you with a different one after the first walkthrough. Every scope, every allowance, every price change arrives as a written change order before work happens. An allowance that isn’t on paper is a surprise waiting for a date. Call (877) 610-1318 to schedule your free estimate, and you’ll get a written line-item quote you can actually compare.
We also offer a Free Second Opinion on Any Written Estimate. If you have a bid from another Plano contractor, bring it to us. We’ll walk the property and tell you honestly whether it covers what it claims, no charge inside the county. And every estimate carries our permanent 10% Senior & Veteran discount.
We Also Serve Cities Near Plano
Based in metro Dallas-Fort Worth and serving Plano and the surrounding communities, our crews work regularly in Lucas, Allen, Murphy, and Sachse. If you live on the edges of Plano near a neighboring city line, don’t worry about the border. We schedule throughout the area, and the same pricing, permits, and 90-Day Done Right Promise apply.
Serving Plano, TX - Our Local Coverage Area
We’re based in the Plano 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 Plano
A room addition in Plano typically costs $45,000-$130,000, while a detached ADU runs $90,000-$220,000 and a garage conversion $30,000-$80,000. Your final number depends on square footage, foundation engineering for the clay soil, finish level, and utility runs. Call (877) 610-1318 for an exact written quote. Estimates are free.
Yes, permits are pulled and inspections signed on every eligible job. Plano is a city where unpermitted work gets caught, and the stop-work orders and fines aren’t worth the shortcut. We handle the full permitting path with the City of Plano, including structural drawings, site plans, and the inspection schedule.
We schedule based on the project queue, and we’ll give you a real start date in writing once the scope and permits are locked. We don’t promise same-day starts on additions or ADUs, because no legitimate contractor does. What we do promise is that when your start date arrives, the crew shows up with a written scope and a uniformed, background-checked team. Call (877) 610-1318 to get on the schedule.
Only if the scope changes, and only in writing. If you change a finish, add a window, or hit a soil condition nobody could have predicted, you’ll receive a written change order before any additional work happens. No surprise invoices at the end. That’s the Barrett & Sons way, and it’s written on every contract.
Yes. We work in every Plano ZIP code, including 75026, 75074, 75075, and 75086, from the 1970s and 1980s tract-home subdivisions east of US 75 to the newer custom homes near Legacy West. If you’re not sure whether we cover your street, call (877) 610-1318 and ask. We’ll tell you straight.
If you’re thinking about adding space to your Plano home, start with a conversation. We’ll walk the property, look at the slab, talk about what you actually need versus what a drawing shows, and put every number on paper before you decide. Call (877) 610-1318 to schedule your free estimate. Our Home Additions & ADU team serves Plano and the surrounding communities with the same written-scope, permit-pulled, fixed-price approach Tom Barrett started in 1998.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Plano and the surrounding Dallas-Fort Worth communities since 1998.