Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Fast, Reliable Home Additions & ADU Across University Park
Adding square footage to a home in University Park is rarely a simple bolt-on job. The city runs its own building department, enforces its own setback and tree-preservation rules, and sits on Blackland Prairie clay that moves every season. A home addition or ADU here typically runs $45,000 to $130,000, and the number that matters most is the one your contractor puts in writing before the first wall comes down. Our Home Additions & ADU team has been building in University Park long enough to know which walls hide knob-and-tube wiring and which piers have settled. Call (877) 610-1318 and we’ll walk the property with you, tape measure in hand, before we quote a single line item.
Why Barrett & Sons Construction Is University Park’s Preferred Home Additions & ADU Company
Tom Barrett founded this company in 1998, and Tom’s sons run the crews. That’s not a marketing line. When you hire us for an ADU or second-story addition in University Park, the person who priced the job is usually the person standing on your job site. We publish our name, our address, and our license number. Look us up. Ask anyone on your street, or look up the license number yourself.
University Park homeowners tend to ask the same set of questions before they sign: Who pulls the permit? What happens when we open the wall and find bad wiring? Will the price change? We answer those questions the same way every time: scope in writing, allowances in writing, change orders in writing. The permit inspector works for you, not for me. If a hidden condition adds cost, you see the number and approve it before we spend a dollar of your money.
Our work in University Park is backed by the 90-Day Done Right Promise, written on every contract. If something isn’t done right, Tom comes back and makes it right, one call. And when you call, a live person answers: 24 hours a day, 7 days a week, not a voicemail box, not an out-of-state call center.
Our Home Additions & ADU Services in University Park
ADU Design & Permitting
Building a detached ADU in University Park means working inside an independent enclave with its own code enforcement. A contractor who pulls a Dallas permit by mistake, because the job address is surrounded by Dallas on every side, gets the addition tagged as unpermitted and the rough-in stopped. We pull University Park permits, and we know how University Park’s urban forestry rules affect what you can build and where. A protected post oak within ten feet of a proposed slab changes the design. That’s not a surprise to us; it’s a line item on the plan we submit.

Garage Conversion ADU
Converting an existing garage in University Park is often the smartest path to a rental unit or mother-in-law suite, and it typically runs $30,000 to $80,000. But the existing slab is the first question. On Blackland Prairie clay, a garage slab poured in 1955 has moved. Wet winters swell the soil; summer droughts shrink it. We check for step cracks and heave before we commit to tying new framing into an old stem wall, because University Park inspectors will check too.

New Detached ADU
On a 7,000 to 9,000 square foot University Park lot, a detached ADU is a geometry problem. Setbacks, impervious-cover limits, and tree-preservation ordinances all constrain the footprint. We’ve designed ADUs here that fit into side yards and rear setbacks that look impossible on paper, and we’ve done it while keeping the mature cedar elms the city protects. A new detached ADU in University Park usually lands between $90,000 and $220,000, depending on size, foundation type, and utility runs.

Junior ADU & Interior Conversion
For homeowners who don’t want to touch the exterior footprint, a junior ADU inside the existing home, such as a converted den with its own entrance and kitchenette, can work well. These conversions often trigger electrical and egress upgrades once the walls open, and University Park’s independent inspection process means those upgrades get enforced. We price the allowance for that work before we start, so the number you approved is the number you pay.

What happens when you call
- 1
A real person answersNo phone trees - you reach a local pro.
- 2
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 University Park
We don’t install mystery materials off the back of a van. On University Park additions and ADUs, we build with brands you can look up: Andersen and Marvin on windows, GAF and CertainTeed on roofing, KraftMaid and Cambria in kitchens. For hardscape tie-ins around a new ADU, we use Belgard and Techo-Bloc. We order directly and schedule delivery around University Park’s narrow lots and alley access, so materials arrive when the crew is ready, not stacked in your driveway for a week.
Common Home Additions & ADU Problems We See in University Park Homes
- Unpermitted work from a previous contractor. University Park’s independent code enforcement is strict, and a prior addition that never had a University Park permit becomes a problem when we apply for new permits. We document what we find and bring it into compliance as part of your scope.
- Knob-and-tube wiring still live inside original walls. On 1930s and 1940s University Park cottages, we regularly find original electrical that was never fully decommissioned. A University Park inspector will require a new subpanel and rewiring once the wall is open for an addition, and we carry an allowance for it in writing.
- Foundation movement from expansive clay. The Blackland Prairie soil under University Park heaves in wet winters and cracks in summer droughts. A new ADU foundation tied incorrectly to an existing slab can open a step crack at the connection within a year. We tie foundations the way University Park inspectors require, not the way a Dallas crew might on the other side of the boundary.
- Protected post oaks and cedar elms limiting design. University Park’s tree-preservation ordinance is not symbolic. A mature post oak near a proposed addition site can force a redesign that a Dallas permit would never ask for across the line. We survey trees early and design around them.
Pricing for Home Additions & ADU in University Park, TX
Here are real numbers for University Park work. A home addition runs $45,000 to $130,000. A detached ADU runs $90,000 to $220,000. A garage conversion runs $30,000 to $80,000.
| Project | University Park Price Range |
|---|---|
| Home Addition | $45,000 - $130,000 |
| ADU Construction | $90,000 - $220,000 |
| Garage Conversion | $30,000 - $80,000 |
What moves the number in University Park specifically: foundation corrections on expansive clay, code-triggered electrical upgrades once old walls open, tree-preservation design changes, and the University Park permit process itself. We write every allowance into the contract. If a hidden condition changes the scope, you approve the change order in writing before we touch it. Call (877) 610-1318 for a free estimate on your University Park addition or ADU.
We Also Serve Cities Near University Park
Our Home Additions & ADU in University Park crews also work in Highland Park, Richardson, Dallas, and Addison. Same owner-operated team, same written change orders, same 90-Day Done Right Promise. If you’re just across the boundary from University Park, the same faces show up.
Serving University Park, TX - Our Local Coverage Area
We’re based in the University Park 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 University Park
Yes, in most cases. University Park’s building department generally requires a structural engineer’s letter and stamped plans when you add a second story over an original pier-and-beam foundation from the 1930s, because the existing footings and joists were not sized for two stories. We coordinate the engineer, pull the University Park permit, and include the engineering cost in your written estimate. Call (877) 610-1318 and we’ll review your specific foundation type.
A protected post oak within 10 feet of the slab will likely require a tree survey and may force you to adjust the design, such as cantilevering the addition or shifting the foundation edge, because University Park’s urban forestry ordinance restricts cutting roots and building within the critical root zone. The city will not approve a permit if the tree protection plan falls short. We start with the tree survey so the answer is known before you spend design money. Call (877) 610-1318 for a free estimate that includes tree review.
Yes, but the footprint will be tight. On a 7,000 sq ft University Park lot, setbacks and impervious-cover rules usually leave room for a compact ADU in the 400 to 800 sq ft range, depending on the existing house footprint, driveway, and protected trees. We map the lot, calculate impervious cover, and design within University Park’s limits before you commit. Call (877) 610-1318 and we’ll bring the tape measure.
University Park code enforcement will require the existing wiring to be brought to current code before the inspection passes, which typically means a new subpanel, rewiring the affected circuits, and sometimes rewiring the original 1930s portion of the home. We carry a written allowance for exactly this in your contract, and if the actual condition is worse, you approve a line-item change order before we proceed. That’s how we keep a University Park addition from becoming a dispute. Call (877) 610-1318 to talk through your specific home’s age and wiring.
A quote changes after demolition because University Park’s housing stock is polarized: original 1930s-1950s brick cottages with hidden knob-and-tube wiring, undersized joists, and clay-driven foundation movement sit next to new custom builds. The quote doesn’t change because we’re careless; it changes when demolition exposes a condition the walls were hiding. We prevent disputes by writing every allowance into the contract before work starts, issuing a written change order with line-item pricing, and getting your approval before we spend a cent on the changed scope. Call (877) 610-1318 and we’ll show you exactly how that looks in a contract.
Let’s Walk Your University Park Property Together
If you’re planning a home addition or ADU in University Park, start with a free estimate from an owner-operated company that’s been serving this community for over 29 years. We’ll inspect the foundation, check the trees, review the University Park permit path, and give you a written line-item quote. Call (877) 610-1318 today, and ask for Tom. He answers his own phone.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving University Park since 1998.







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