Service
Room Additions in Southlake, Keller & DFW
Primary suite additions, second-story expansions, sunrooms, in-law suites, and casita builds across Southlake, Keller, Westlake, Colleyville, Trophy Club, and Flower Mound. Chad partners with your designer (or one we introduce) on every addition.
A room addition at Swanson typically covers 250-950 square feet of new conditioned square footage — a primary suite, a second-story addition above an existing single-story portion, a sunroom or three-season addition off the back, or a detached casita/pool house. Most DFW luxury additions run 16-32 weeks of active construction and land in the $250,000 to $750,000 range. Foundation and roofline complexity, ARB review timelines, and finish tier drive most of the variance.
What a room addition looks like at Swanson.
A room addition is a different animal than an interior remodel. You’re not changing the home you already have — you’re growing it. Different foundation work. Different structural engineering. Almost always an HOA architectural review. And often a longer timeline than the same-scope interior remodel would take, because you’re building shell-plus-finish rather than just finish.
The trade-off, when the scope is right, is that the family stays in the house throughout and the finished space is exactly the size the home actually needs. No compromises to fit within existing walls. No load-bearing pattern to work around. And when it’s done, the new addition reads as if the home had always had it — because the roofline, the materials, and the proportion tie back to what was already there.
Five scopes we run most often.
Primary suite addition.
The most common scope. A typical Swanson primary suite addition adds 450-700 sq ft — bedroom, spa-grade primary bath, walk-in closet, sometimes a sitting nook. The existing primary usually becomes a guest suite or office. Budget: $250K-$450K. Timeline: 16-24 weeks construction. Common when the original primary was small, poorly oriented, or distant from where the family actually spends time.
Second-story addition.
When the lot is tight and you need square footage without expanding the footprint. Typical second-story addition adds 700-1,200 sq ft — often a new primary suite plus a bonus room, or two bedrooms and a bath. Requires a structural engineer’s review of the first-floor bearing walls; sometimes we rebuild portions of the first-floor ceiling framing to carry the new load. Budget: $500-$650/sq ft. Timeline: 22-32 weeks construction.
Sunroom or three-season addition.
A conditioned or semi-conditioned addition off the back — glass-heavy, oriented for the view, integrated with the kitchen or family room. Between 200-450 sq ft. Budget: $185K-$385K depending on whether it’s a fully conditioned four-season addition or a three-season addition with limited HVAC. Timeline: 14-22 weeks.
In-law / guest suite addition.
Bedroom, private bath, and often a kitchenette — either attached to the main home or as a detached casita on the property. 400-700 sq ft. Budget: $325K-$550K. Timeline: 18-26 weeks. Common in multi-generational households or homes with regular long-term guests.
Pool house / detached casita.
A 250-650 sq ft freestanding structure — full bath, small bar or kitchenette, changing area, sometimes an office nook. Same finish grade as the main home. Budget: $275K-$550K depending on size and whether the interior is full-conditioned living or lighter pool-house use. Timeline: 16-22 weeks.
What’s included in a Swanson room addition contract.
- Design coordination. We work with your designer (or introduce you to one we trust) to develop the addition’s interior design in parallel with the shell design. The interior finish plan is locked before framing begins so the shell dimensions match the interior intent.
- Architectural drawings. Complete construction documents — foundation plan, framing plan, elevations, sections, roof plan, MEP schematics. Prepared by our architect partners.
- HOA architectural review + permits. We draft the ARB submission package, respond to feedback, resubmit if requested. Then all permits (building, electrical, plumbing, mechanical, gas).
- Foundation. Slab-on-grade in most cases; pier-and-beam or raised foundation when the site or design requires. Drainage and grading integrated.
- Framing + roofing. Wood-framed walls, engineered lumber for spans that need it, roof framing tied into the existing home’s rooflines. Roofing to match the existing home (composition, tile, metal — whichever the home already has).
- Exterior finishes. Stucco, stone, brick, siding — matched to the existing home’s exterior. Windows and doors matched or upgraded coordinated with your designer’s spec.
- Full MEP. New HVAC zone, electrical service extension, plumbing to the new bath/kitchen, gas if needed.
- Interior finish-out. Everything from insulation and drywall through paint, trim, flooring, cabinetry, tile, and fixtures — coordinated with your designer’s spec sheet.
- Project management. BuilderTrend daily updates, weekly site walkthroughs with you and your designer, single point of contact (Nancy).
- Site protection + cleanup. Ram-board flooring in the existing home’s traffic corridor to the addition site, zip-wall dust barrier at the tie-in point, daily cleanup.
Recent addition projects.
Southlake Master Suite Addition — a representative primary suite addition on a Southlake lot with ARB review.
Ready to talk about your room addition?
Talk to Chad about your project — the first conversation is sixty to ninety minutes in your home, free, no pitch. Bring your designer if you have one; we can help you find one if you don’t.
Frequently asked questions
What kinds of additions do you build?
What does a room addition cost in Southlake or Keller?
How long does a room addition take?
Can we stay in the house during a room addition?
Do you handle HOA architectural review?
What's the ARB process actually like?
Do you do primary suite additions specifically?
What about second-story additions?
Do you do additions in Vaquero, Carillon, and Timarron?
Inquire
Talk to Chad about your room additions.
First conversation is sixty to ninety minutes in your home. Free, no pitch.
Inquire