Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Fast, Reliable Home Additions & ADU Across Bellaire
Most home additions in Bellaire run $45,000 to $130,000, while a detached ADU typically lands between $90,000 and $220,000. You won’t get a straight answer like that from every contractor, but you’ll get one from us. If you’re planning a Home Additions & ADU project in the 77401 or 77402 zip codes, call (877) 610-1318 for a free estimate. We know Bellaire’s permit office, its flood rules, and its lot coverage math better than most shops running jobs here from across the county line.
Why Barrett & Sons Construction Is Bellaire’s Preferred Home Additions & ADU Company
Tom Barrett founded this company in 1998, and his sons run the crews. We’re not a franchise dispatching strangers from three states away. When you call, a live person answers, day or night. When work happens in Bellaire, one of the Barretts is on-site most days, checking elevations, walking the slab before the pour, and making sure the inspector leaves with a signature, not a red tag.
Bellaire homeowners have a specific set of worries, and we’ve heard them all. A reader once told us he spent six months fighting Houston-based permitting assumptions on a Bellaire lot before he called us. That’s the kind of frustration we’re built to avoid because we already know the city’s rules on impervious surface, setbacks, and post-Harvey finished-floor elevations. Ask anyone on your street, or look up the license number yourself. Tom publishes it. That’s the point of a name on the truck.
Our Home Additions & ADU Services in Bellaire
ADU Design & Permitting
Detached ADUs in Bellaire are not a simple Houston-style filing. The city’s independent building department reviews your site plan against its own impervious-surface and setback standards, not Harris County’s. We handle the design, the drainage calcs, and the plan review from start to sign-off so your ADU doesn’t stall at city hall for months. Call (877) 610-1318 and we’ll walk the lot with you first.

Garage Conversion ADU
Converting an attached garage in Bellaire means checking two things most contractors skip: the finished-floor elevation under the city’s post-Harvey floodplain rules, and your HOA’s architectural guidelines if you’re in one of the newer subdivisions. We run both before we draw anything. A typical Bellaire garage conversion runs $30,000 to $80,000, and we write every allowance and change order in paper form before work starts.

New Detached ADU
If you have the lot depth for a stand-alone unit, Bellaire’s lot coverage limits will govern how big it can be. We design within those limits, not against them. On a 1960s ranch on the 5200 block of Bissonnet Street, our crew added a 500-square-foot primary suite without re-triggering drainage review by working the impervious-surface math early. That’s Bellaire-specific experience you can’t fake.

Junior ADU & Interior Conversion
Interior ADUs, like a converted den or bonus room with a kitchenette, often move faster because they don’t add building footprint. But they still need separate meter considerations, egress windows, and in many Bellaire homes, careful plumbing routing through the existing slab. We’ve done enough of these in the 77401 zip code to know where the surprises hide.

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.
- 3
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 Bellaire
We install materials you can look up. For ADU kitchens and baths, we work with Schluter for waterproofing and Sterling for tub and shower bases because both hold up under Bellaire’s humidity and the occasional slab shift. We also carry GAF on roofing tie-ins where a new addition meets the existing structure. You won’t get mystery brands off a van with us.
Common Home Additions & ADU Problems We See in Bellaire Homes
- Houston setback assumptions getting red-tagged. Bellaire’s lot coverage and impervious-surface rules are stricter than Houston’s. Plans drawn for Houston definitions fail Bellaire review, and the permit stalls until you redraw them. We draw for Bellaire from day one.
- Voiding a builder’s warranty on newer homes. On post-2010 builds in Bellaire’s newer pockets, cutting into structural systems without reading the HOA’s architectural rules and the builder’s change-order requirements can void the warranty. We read both before we cut.
- Post-Harvey finished-floor elevation failures. If a second-story addition’s foundation height doesn’t meet the city’s floodplain sign-off under the post-Harvey BFE standards, the permit stops. We check the elevation certificate before plans go in.
- Drainage and impervious-surface surprises. Bellaire sits inside the Brays Bayou watershed. Adding square footage almost always triggers stormwater detention review. We calculate that before you spend money on plans that won’t pass.
Pricing for Home Additions & ADU in Bellaire, TX
Home addition costs in Bellaire are driven by three things: foundation work (slab raising for flood compliance is common), the city’s permit and inspection timeline, and material availability for the brands we install. Here’s what to expect in current Bellaire market numbers:
| Project | Typical Bellaire Range |
|---|---|
| Home Addition | $45,000-$130,000 |
| ADU Construction | $90,000-$220,000 |
| Garage Conversion | $30,000-$80,000 |
| Second Story Additions | $45,000-$130,000 |
| Sunrooms & Enclosed Patios | $45,000-$130,000 |
We write a fixed, line-item estimate before any work starts. If something changes, you get it in writing before the nail moves. Call (877) 610-1318 for the free estimate. Seniors and veterans always get 10% off.
We Also Serve Cities Near Bellaire
Our Home Additions & ADU in Bellaire work extends across West University Place, Houston, Alief, and Aldine. Same crews, same written change orders, same 90-Day Done Right Promise on every job. If you’re a few minutes outside the city line, the estimate is still free.
Serving Bellaire, TX - Our Local Coverage Area
We’re based in the Bellaire 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 Bellaire
Yes, Bellaire requires a separate building permit for any ADU above a garage, regardless of the home’s age, and the city reviews it under its own independent building code, not Houston’s. If your subdivision has an HOA, you’ll also need their architectural approval before plan review, because the city won’t look at HOA rules, but the HOA can fine you for skipping them. We pull the permit and coordinate the HOA paperwork. Call (877) 610-1318 for the exact sequence on your lot.
If your garage slab sits below the current Base Flood Elevation for your Bellaire block, a conversion to living space usually requires raising the finished floor, adding flood vents, or both. That changes the budget and sometimes kills the project at the feasibility stage. We check the elevation certificate before you commit a dollar to plans.
A builder’s implied warranty on a 1950s Bellaire ranch is effectively gone, but if the home has had structural upgrades or a recent foundation repair warranty, cutting into load-bearing walls can void it. We review any active warranty language before the demo starts and coordinate the load-bearing work with Bellaire’s third-party inspector. Get your free estimate by calling (877) 610-1318.
A 600-square-foot primary suite in Bellaire typically falls between $75,000 and $130,000, with the slab raising and stormwater compliance adding meaningful cost to the low end of the range. The city’s finished-floor and drainage review is not a formality here. Call (877) 610-1318 for a line-item price on your specific block.
Yes, Bellaire requires rough-in inspections for framing, electrical, plumbing, and mechanical before drywall on an ADU, and passing all of them in sequence is what moves your draw schedule forward. We structure the payment draws around Bellaire’s actual inspection checklist, not a generic one, so you’re not paying ahead of work the city hasn’t signed off on yet. That’s how the Bissonnet Street suite job got a punch-list-free sign-off.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Bellaire since 1998.







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