Plenty of homes in Starr County are never really finished. A bedroom goes on when the family grows, the carport becomes a den, a casita appears out back. Home construction in Rio Grande City is often that kind of steady, room-by-room building, and we work with families at every stage of it.
What sets our crew apart is that air conditioning is our main trade. Additions are where cooling most often goes wrong: a new room hung off the end of an old duct run, or a window unit stuck in the wall because nobody planned anything else. We design the AC with the room, not after it.
Room additions, remodels and finish-out work
These are the kinds of residential construction projects we take on:
- Room additions. Bedrooms, bathrooms, living space and enlarged kitchens, built in concrete block or wood frame to match the house.
- Enclosures and conversions. Turning a carport, porch or garage into heated and cooled living space.
- Interior remodels. Moving or removing non-bearing walls, updating kitchens and baths, new flooring, doors and trim.
- Finishing owner-built homes. Picking up a project mid-way with framing, roofing, insulation, drywall, trim and paint.
- Small outbuildings. Casitas, workshops and storage buildings on a new slab.
Concrete, painting and carpentry are all in-house trades for us, so the slab from our concrete work crew and the finish paint come from the same team that framed the walls.
Design decisions that shape an addition
Foundation and walls
A new room needs a foundation that works with the house it attaches to. On caliche and clay soils, that means proper footings, a compacted base and steel dowels into the existing slab so the two move together. Block construction is common here and handles heat and humidity well; frame construction can be faster and easier to insulate. We will walk you through the trade-offs for your lot.

Roof tie-in
Where the new roof meets the old is where leaks start. Matching the pitch, framing a solid connection and flashing the seam correctly matters more than which roofing material you pick.

Sun, insulation and windows
West-facing walls and big unshaded windows take the hardest afternoon heat. Placing windows with that in mind, insulating walls and ceilings well and choosing a light roof color all reduce how much cooling the room needs.
Air conditioning for the new space
We start with a load calculation, an estimate of how much heat the room gains, rather than a guess based on square feet. Then we check whether your existing system has spare capacity. If it does not, which is common with older units sized for the original house, a dedicated ductless system is often the better answer. Our mini-split installation team roughs in the lines and drain before drywall, and for whole new homes our new construction HVAC service plans the full system from the foundation up.

Do you need a permit, and who does each trade?
Permits depend on location. Rio Grande City runs its own permitting for property inside the city. Properties in unincorporated parts of the county follow Starr County's rules. Requirements change over time, so check with the City of Rio Grande City or Starr County for your address before work starts, and ask about floodplain rules if your lot sits near Arroyo Los Olmos, another arroyo or the river.
Texas licenses specific trades at the state level. Air conditioning and electrical contractors are licensed through TDLR, and plumbers through the Texas State Board of Plumbing Examiners. Your estimate will spell out which trades are involved in your project and who is doing that work, so you can check any license yourself. Texas has no state licence for general contractors, which makes those trade licences the thing to verify.
Three more rules come up on most projects. Footing trenches count as excavation, so under Texas law, as Texas811 describes it, utilities must be requested through 811 two business days ahead. Remodeling a home built before 1978 can disturb lead paint, and paid work over the EPA's thresholds falls under its Renovation, Repair and Painting rule. Inside city limits, Texas cities generally build to the International Residential Code, whose mechanical chapter (section M1401.3) calls for heating and cooling equipment to be sized from loads calculated with ACCA Manual J or another approved method, the same approach we use for the new room.
How a project moves from idea to move-in
- Site visit and scope. We look at the house, the lot and what you want, and talk through budget priorities.
- Plan and estimate. Layout, materials, AC approach and a written scope with a schedule.
- Permits. Applied for with the city or county where required.
- Foundation. Excavation, footings, steel and slab.
- Walls and roof. Block or framing, roof tie-in and dry-in so weather stays out.
- Rough-ins. HVAC lines and drains, electrical and plumbing by the appropriate licensed trades, followed by any required inspections.
- Insulation, drywall and finish. Doors, trim, flooring, paint and fixtures.
- AC start-up. The new system is charged, tested and set up, and we show you how to run it.
Timelines depend on the size of the project, weather, inspection schedules and material availability. We give you a realistic schedule with the estimate and keep you posted when anything moves.

What determines the cost of building or remodeling
Every project is priced from its own plan. The biggest factors are:
- Square footage and the number of rooms involved.
- Foundation type and how much site prep the lot needs.
- Block versus frame, and the complexity of the roof tie-in.
- Finish level, from basic materials to custom tile and cabinets.
- The cooling approach, such as extending ducts versus adding a mini-split.
- Permit and inspection requirements for your location.
- Whether the work is done in one stretch or in phases as budget allows.
- Electrical service upgrades if the panel cannot carry the new room and its AC.
- Demolition and haul-off when a carport, porch or old wall has to come out first.
Financing is available; ask us for details when you request an estimate. Installed equipment and materials carry their manufacturers' warranties. We build and remodel in West Alto Bonito, B and E, Valle Vista and communities across Starr County.
Why families build with 956 Multi Service
Most additions involve four or five trades, and the cooling is the one most often left for last. With 956 Multi Service, the concrete, block or framing, drywall, paint and air conditioning come from one small Rio Grande City crew, and the AC is part of the drawing from the first visit.
The company has been in business since July 2024 and holds a 5.0 average across 41 Google reviews. Addition estimates get booked over the phone, which we pick up from eight in the morning to seven in the evening except on Sundays. Cash, all four major cards and financing are available, which helps families who build in phases.
Google reviews that mention work like home construction & remodeling
5.0 out of 5 from 41 Google reviews
“Very clean work and good service”
“After my mr. Cool Mini split ac went out nd Mr. Jesus Cantu was notified for Assistance, he suggested and advised on a confort AC mini split 2 ton Unit to cool off my living Quarters. Awesome results , Quick installation and proficient professional job . Very efficient and professional your man . Would recommend to Rio Grande Vally Whole..heartedly. don't fight the heat notify Jesus Cantu.”
“Very great customer service! Talked to them over the phone to explain my A/C situation I was having, and they knew what the problem was right away! Came to fix the problem in a timely manner! Recently I purchased a new unit and they went for an installation the same day! Highly recommended!”
What do homeowners ask before building or remodeling in Rio Grande City?
Do you build room additions and handle the AC for them?
Yes, and planning the cooling early is the main reason people call us for additions. We look at the size of the new room, its windows and sun exposure, and what your current system can actually handle. Sometimes extending ductwork works. More often a separate ductless mini-split is the cleaner choice. Either way, the lines, drain and power get roughed in before the walls are closed.
Can you help owner-builders finish a home?
Yes. Many homes around Starr County are built in stages by their owners, and we can pick up wherever you are. That might be framing and roofing a room you started, insulating and hanging drywall, installing trim and doors, painting, pouring steps or a patio, or putting in the air conditioning. We will look at the work already done and tell you honestly what needs attention before finishing over it.
Do I need a permit for an addition in Starr County?
It depends on where the property is. Rio Grande City handles permits inside its city limits, while unincorporated parts of Starr County follow county rules. The requirements, inspections and fees can differ, so check with the City of Rio Grande City or Starr County before work starts. If your lot is near an arroyo or in a mapped flood zone, ask about floodplain rules at the same time.
Should a room addition be block or wood frame?
Usually whichever matches the house, unless there is a strong reason not to. A block home in Rio Grande City generally gets a block addition so the walls, stucco and roof line read as one building. Frame goes up faster and is easier to insulate and run lines through, which helps a bedroom that needs its own mini-split. We price both when the choice is close.
Can we live in the house while you build or remodel?
In most additions, yes, because the new room is built outside the existing walls until the final opening is cut. Kitchen and bathroom remodels are harder to live around, so we plan those in phases and keep one working bathroom whenever possible. Dust walls, a covered path through the house and a set daily schedule make it easier on the family.
Still have a question about home construction & remodeling? Ask us directly.
Call (213) 423-7827Where we handle home construction & remodeling
- Home Construction & Remodeling in West Alto Bonito, TXNewer owner-built block homes here grow one addition at a time, each needing its own cooling plan.
- Home Construction & Remodeling in B and E, TXOwner-built homes that grow room by room make a mini-split zone cheaper than stretching old ductwork.
- Home Construction & Remodeling in Valle Vista, TXHomes spread along caliche roads north of La Grulla often add casitas or bedrooms on roomy lots.
- Home Construction & Remodeling in Starr CountyColonia and rural homes across the county are often built in stages as the family and budget allow.
- Home Construction & Remodeling in Mi Ranchito Estate, TXFamilies pairing a mobile home with a newer add-on need the two tied together with steps, roofs and cooling.
- Home Construction & Remodeling in El Refugio, TXLower ground toward the river means an addition slab may need to sit higher than the original house.
- Home Construction & Remodeling in Olivia Lopez de Gutierrez, TXLarger lots off farm roads leave room for workshops and casitas with their own long line-set runs.
- Home Construction & Remodeling in Garza-Salinas II, TXClosely spaced lots leave little yard, so additions are planned around tight side and back spaces.
- Home Construction & Remodeling in La Homa, TXSelf-built homes and manufactured houses on rural lots here often need finish-out help and room additions.
- Home Construction & Remodeling in Alton, TXOne of Hidalgo County's fastest-growing cities, where new and expanding homes need properly sized first systems.

