Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Fast, Reliable Home Additions & ADU Across Frisco
A home addition in Frisco typically costs between $45,000 and $130,000, while a full detached ADU runs $90,000 to $220,000 depending on size, finishes, and site work. Most projects take 4 to 10 months from permit submittal to final inspection, with Frisco’s Building Inspections department shaping a meaningful part of that timeline. We know exactly what that process demands in this city because we’ve navigated it hundreds of times.
At Barrett & Sons Construction, we’ve built and converted living space all over Frisco, from the 75035 corridor near Stonebriar Centre to newer pockets west of the Dallas North Tollway in 75033 and 75034. If you’re weighing an addition against moving, or an aging parent needs a place on your property, call (877) 610-1318. We’ll walk the site with you, listen first, and give you a written, line-item scope before anything gets signed.
Why Barrett & Sons Construction Is Frisco’s Preferred Home Additions & ADU Company
Tom Barrett started this company in 1998, and his name still sits on the side of every truck that pulls up to a job in Frisco. That matters because when you call our office, a live person answers, and when you have a question about your addition, you don’t chase a call center. You get someone who knows your project, your street, and your HOA submittal status.
Frisco reviewers consistently point to the same two things: we show up when we say we will, and we put every change on paper before it happens. The permit inspector works for you, not for us, and we treat that relationship with respect on every job from a garage conversion off Eldorado Parkway to a second-story addition near Warren Sports Complex. We pull permits on every eligible job, schedule the inspections, and stand next to you while they’re signed off.
We also understand Frisco’s HOA review process better than most contractors. Master-planned communities like those along Coit Road and Main Street can hold exterior work for weeks if submittals are incomplete, so we build that time into the schedule and handle the paperwork as part of our scope.
Our Home Additions & ADU Services in Frisco
Our Home Additions & ADU team handles everything from small bump-outs to full detached units. Here’s how each service typically plays out in Frisco.
ADU Design & Permitting
Frisco’s building department requires architectural drawings, structural engineering, and site plan review before an ADU permit issues. We prepare those documents, coordinate the engineering, and carry the submittal through the city’s back-and-forth review cycle. In our experience, a well-prepared Frisco ADU package clears permit in 6 to 10 weeks once drawings are complete, and we flag code issues before the city does.

Garage Conversion ADU
Converting an attached garage runs $30,000 to $80,000 in Frisco, and it’s the most common ADU path for homes in the 75034 ZIP because the slab, walls, and roofline already exist. Frisco’s inspectors scrutinize garage conversions closely on HVAC separation, egress windows, and fire ratings, so we design to those requirements from day one rather than fixing rejected work mid-job.

New Detached ADU
A new detached unit in a Frisco backyard typically runs $90,000 to $220,000, and on the Blackland Prairie, site prep and foundation engineering drive a large share of that number. We recommend helical piers or drilled piers on most Frisco lots, and we include written allowance sheets for every finish so a surprise never lands on your final invoice.

Junior ADU & Interior Conversion
A junior ADU can be carved out of an existing floor plan, often from a formal dining room, bonus room, or oversized bedroom with a private entrance. In Frisco’s early-2000s production homes, we frequently see open-concept plans that adapt well to this approach, and it’s usually the most cost-effective way to add a legal dwelling unit without committing to a full detached build.

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 Frisco
We build with materials you can verify. On Frisco ADU and addition projects, that often means Techo-Bloc or Cambridge Pavers for hardscape and patio areas around a new unit, and Quikrete products for foundation-related work. We don’t install mystery brands off a van, and we’ll name every product in your written scope before you sign. If you’d rather see the material in person, we’ll point you to a local Frisco supplier and even meet you there.
Common Home Additions & ADU Problems We See in Frisco Homes
- Expansive clay heave under new ADU slabs. Frisco’s montmorillonite clay absorbs moisture in wet springs and contracts hard through triple-digit summer droughts. A poorly engineered slab will crack within the first three seasons. We spec pier depth and slab reinforcement to the city’s requirements, not to the lowest bid.
- HOA architectural review delays. In Frisco’s master-planned communities, a missing elevation drawing or a fence detail that conflicts with community standards can stall an exterior addition for weeks. We compile complete HOA submittal packets as part of every job where exterior work is proposed.
- Permit headaches on previously unpermitted work. We regularly see enclosed patios and garage conversions in Frisco that were done without permits, and when a homeowner wants to add on legally, the city requires the old work to be brought up to code first. That’s not a surprise we let hit you mid-job; we inspect for it during estimating.
- Foundation movement in 15- to 25-year-old homes. Most of Frisco’s “older” housing stock was built in the 2000s, and we already see slab movement and brick veneer cracking from the clay. We won’t frame an addition on a moving foundation; we’ll put the correction in scope, in writing, and explain exactly why it’s necessary.
Pricing for Home Additions & ADU in Frisco, TX
A room addition in Frisco typically lands between $45,000 and $130,000. Garage conversions run $30,000 to $80,000. A new detached ADU falls between $90,000 and $220,000, and a junior ADU or interior conversion usually comes in below those figures, often in the $50,000 to $90,000 range depending on plumbing and electrical scope. For every one of these, we hold fixed pricing with written change orders only, and we will not start a change that isn’t on paper. If you’re considering an addition alongside a kitchen redo, our Kitchen Remodeling in Frisco work follows the same rule.
Call (877) 610-1318 and we’ll build you a line-item quote for your exact scope, with allowances noted and no trip charge inside the county.
We Also Serve Cities Near Frisco
We work throughout Frisco and into the surrounding communities that share the same clay soil challenges, HOA processes, and North Texas building seasons. That includes Prosper, The Colony, Little Elm, and Celina. If you’re just over the city line, the same crew, pricing discipline, and 90-Day Done Right Promise apply. We also handle Bathroom Remodeling in Frisco for homeowners who want to improve existing square footage while planning an addition.
Serving Frisco, TX - Our Local Coverage Area
We’re based in the Frisco 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 Frisco
We answer the phone 24 hours a day, 7 days a week, and a live person takes your call. For a new addition or ADU project in Frisco, we typically schedule a site visit within a few business days, then deliver a written line-item estimate within two weeks of that visit. You’ll wait a bit for the estimate, because we’re measuring, checking foundation conditions, and reviewing HOA requirements, not guessing. Call (877) 610-1318 and we’ll put you on the schedule.
We serve all of Frisco, including 75033, 75034, and 75035. Our crews have worked communities along Eldorado Parkway, Coit Road, Main Street, and the Dallas North Tollway corridor, and we’re familiar with the HOA review processes in the city’s largest master-planned subdivisions. If you’re in Frisco, you’re in our service area.
Yes, on every eligible job, no exceptions. Frisco’s Building Inspections department is known across DFW for strict, consistent enforcement and mandatory third-party engineering documentation on foundation and structural work. Contractors who cut corners on permits in other cities get flagged fast in Frisco, and we don’t build that risk into your project. The permit inspector works for you, not for us, and we want that inspection signed off before you write the final check.
Three reasons. First, Frisco’s expansive clay soils require deeper foundation engineering than cities built on more stable ground, and pier depth and slab reinforcement add real cost. Second, the city’s permitting and inspection standards are stricter than most neighboring municipalities, which means more engineering and documentation up front. Third, HOA architectural review in many Frisco communities adds process steps and required documentation that a project in an unincorporated area would never face. You’re paying for a unit that will stand straight and pass every inspection, not for a unit that gets built fast and defended later.
Every job carries our 90-Day Done Right Promise, written on the contract. If something isn’t right within 90 days, Tom Barrett comes back and makes it right with one call. Beyond that, we pass along manufacturer warranties on materials like pavers and structural products, and we stand behind our workmanship because we live in the same North Texas market you do. If there’s a problem, you call the same number, and the same people answer.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Frisco and the surrounding North Texas communities.







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