A lot of "my AC isn't keeping up" calls in Rio Grande City turn out to be a duct problem, not an equipment problem. The unit outside is cooling just fine, but a run in the attic has dropped off its collar, a flex line is folded flat behind the water heater closet, or the belly of a mobile home has been opened up by animals. Ductwork repair in Rio Grande City starts with finding where the cold air is going instead of into your rooms.
This page covers air duct repair, flex duct replacement and new ductwork installation. Two related services have their own pages: duct sealing and duct insulation for leaky joints and sweating runs, and air duct and dryer vent cleaning for dust, debris and pest contamination.
What duct repair and replacement work includes
Ductwork is the supply side that carries cooled air from the air handler to each room, plus the return side that brings room air back. A job can be one run clipped back onto its collar or every attic run replaced and resized. The work covers:
- Supply and return runs: reconnecting, re-strapping or replacing flex and sheet-metal sections, including the return box.
- Plenums, collars and boots: the fittings where runs leave the air handler and where they end at the ceiling.
- Belly and crossover ducts: trunk repairs, crossover reconnections and closing torn belly wrap on manufactured homes.
- Additions and conversions: new runs sized for a garage conversion or a room built onto an older house.
- Registers and grilles: replacing rusted or broken covers.
- Before-and-after readings: airflow and static pressure, so the change is measured.
What failing ductwork looks and feels like
You rarely see ducts, so the symptoms show up in the rooms. This table matches what people tell us on the phone to the duct fault that usually causes it.
| What you notice | Likely duct cause | How soon to act |
|---|---|---|
| One bedroom or an addition stays hot | Undersized, kinked or disconnected run to that room | Soon, it gets worse in July and August |
| Air barely moves at a far vent | Long sagging flex run or crushed section | Soon |
| Dust or insulation fibers puffing from a register | Torn return or supply pulling attic air | Now, you are breathing attic dust |
| Water spots on the ceiling near a vent | Condensation on an uninsulated or leaking duct | Now, drywall and mold damage follow |
| Bills keep rising, AC runs constantly | Leaks dumping cooled air into the attic or belly | Soon |
| Rattling, whistling or a flapping sound overhead | Loose connection or collapsed liner | When convenient, but check it |
Why attic and belly ducts break down in Starr County heat
Attics here bake. On a 100°F afternoon the air above the ceiling can be far hotter than the yard, and the ducts sit in that every day from spring through fall. Flex duct, the round insulated tube used in most local homes, has a plastic inner liner and a thin outer jacket. Years of that heat make both brittle, and the tape or straps holding the joints start to let go.
Hanging is the other big factor. Flex is supposed to be supported every few feet and pulled reasonably straight; Department of Energy guidance calls for a strap at least every 4 feet and at each bend. When it is laid loosely across joists, it sags, bunches at bends and loses airflow. Ducts also get stepped on, crushed under stored boxes or pushed aside by whoever ran cable or plumbing last.
Manufactured homes have a different weak point. The main trunk runs inside the belly, the insulated underside of the home, and double-wides add a crossover duct between halves. Torn belly wrap lets in heat and critters, and a crossover that slips off its collar can dump half the cooling under the floor. Many owner-built block and frame homes in the area have a different issue: rooms added over the years were teed off an existing trunk that was never sized for them.
Repair, reseal or replace: what does your duct system need?
Not every duct problem calls for new ducts. The right answer depends on how much of the system is damaged and how it was laid out.
Air duct repair for isolated damage
When one or two runs have fallen, kinked or separated, we reconnect them, re-hang them on straps and replace short damaged sections. This is the fastest fix and often happens in a single visit when the material is on the truck.
Attic duct replacement with new flex
If the liner is cracking in several places, insulation is falling apart or most runs are sagging, patching becomes a losing game. Replacing the flex throughout the attic gives you new insulation on every run and a chance to correct sizes and routing.
New ductwork installation for additions and new systems
A room addition, a converted garage or a new central system may need ducts designed from the start. That means working out how much air each room needs, sizing supply and return runs, and placing registers so air actually mixes in the room. Pairing this with AC replacement lets equipment and ducts be matched. For single-wides and double-wides, see our page on mobile home AC.
A ductwork visit, step by step
- Talk through the symptoms. Which rooms, what time of day, any recent work in the attic.
- Measure at the registers. Air temperature and airflow at each vent show where the system is short.
- Inspect the attic or belly. We look at every reachable run, joint, boot and the plenum (the box on the air handler that feeds the ducts), and take photos you can see.
- Check pressure. A static pressure reading tells us whether the ducts are choking the blower.
- Explain the options. Repair, partial replacement or full replacement, with the reasons for each.
- Do the work. A small repair is often done on the first visit if the day's schedule has room. Larger replacements are booked for a full day so the attic work is done early, before it gets dangerously hot.
Why homeowners call 956 Multi Service for duct problems
Founded in Rio Grande City in July 2024, our crew works in attics and mobile-home bellies across Starr County, and our Google profile shows 5.0 stars from 41 reviews that often mention on-time technicians who explain their findings. Call any day but Sunday between 8 AM and 7 PM. The same people service the AC, so a duct fault found on a repair call needs no second company, and small fixes frequently wrap up that day. Cash is fine, so are Visa, Discover, American Express and MasterCard, and financing can cover a bigger replacement.
What changes the cost of duct work
We do not quote duct jobs by phone because the price depends on what is actually in the attic. The main factors:
- How many runs are involved, and whether returns as well as supplies need work.
- Access. A tall attic with a walkway is quicker than a low-pitch roof or a belly with tight clearance.
- Duct size changes if rooms are under-served, which can mean new collars, boots or a new plenum.
- Insulation level of the replacement duct.
- Registers, grilles and boots that are rusted or broken and need replacing too.
- Timing with other work, such as a new AC or attic insulation, which can share labor.
- Belly access on manufactured homes, where skirting has to come off and torn wrap has to be patched or replaced after the duct is fixed.
To keep new ducts healthy, keep storage off them, change filters on schedule and check mobile-home belly wrap after big storms.
Texas licensing, permits and duct code basics
Texas requires a TDLR air conditioning licence for HVAC work, including duct systems connected to it. Before hiring anyone, you can look up their licence on the Texas Department of Licensing and Regulation website. TDLR also notes that people exempt from registration still need any city permits and inspections.
Permit rules are local: incorporated cities run their own building offices and unincorporated Starr County differs, so check before a whole-system change. In manufactured homes, the factory ducts and crossover were built to HUD's construction standards (24 CFR Part 3280), and repairs should keep those joints sealed and supported.
Ductwork: pick the service you need
Google reviews that mention work like ductwork
5.0 out of 5 from 41 Google reviews
“Both gentlemen arrived punctually and were exceptionally well mannered and explained the whole process. They diligently completed the service I needed and delivered an exceptional job! I will definitely reach out to them again for any future work I may need. Highly recommend!”
Response from the owner: Thank you 💯
“Great service!! They were very responsive and helpful, and they were able to resolve my issue quickly. I would definitely recommend this company to others.”
“Great work, very detailed, clean and efficient job well done. 10/10 would recommend anyone needing minisplit work or any other work around the house.”
What do Rio Grande City homeowners ask about their ducts?
How do I know if my ducts are leaking?
Look for rooms that run warmer than the rest, weak air at the far vents, dust lines around ceiling registers and bills that climb while the AC never seems to rest. In the attic, gaps at joints, loose tape, crushed runs or wet spots on the duct jacket are giveaways. Under a mobile home, torn belly wrap is the usual clue. A technician can confirm with airflow and pressure readings.
How long does attic ductwork last in South Texas heat?
There is no fixed number. Flex duct in a hot attic usually shows wear sooner than sheet metal because the liner and outer jacket get brittle, and straps, tape and connections loosen with years of heating and cooling. Some systems hold up well for a long time, others fail early because of poor hanging or foot traffic. Condition at inspection matters more than age.
Can you replace ducts without replacing the AC?
Yes. If the condenser and air handler are healthy, the ducts can be replaced on their own and connected to the existing equipment. It is also a sensible time to check that the duct sizes match what the blower can move. If the AC is near the end of its life, doing both together saves a second trip into the attic and lets the new system be matched to new ducts.
Do you repair ductwork under mobile homes?
Yes, belly duct work is a regular part of ductwork repair in Starr County. Common fixes include reconnecting a separated trunk or crossover duct, replacing a damaged section, sealing joints and closing up torn belly wrap so pests and outside air stay out. Access depends on skirting and clearance under the home, which we check first.
Is it better to repair or replace old ductwork?
It depends on how much is damaged. When a few runs are crushed or loose and the rest of the liner and jacket are sound, repair is the better value. When the flex is brittle in many places or the layout never fed the far rooms, replacing the attic runs makes more sense. Photos from the attic or belly show you which case you are in.
Still have a question about ductwork? Ask us directly.
Call (213) 423-7827Where we handle ductwork
- Ductwork in Mikes, TXCrushed or disconnected belly ducts under manufactured homes are the usual cause of weak airflow in Mikes.
- Ductwork in La Grulla, TXOlder La Grulla frame houses lose cooling through hot, leaky attic runs.
- Ductwork in Perezville, TXWeak vents in Perezville homes usually trace back to aging attic flex.
- Ductwork in B and E, TXB and E additions are often teed off an old trunk never sized to feed them.
- Ductwork in Mi Ranchito Estate, TXA mobile home plus an add-on can mean belly ducts and attic runs on one lot.
- Ductwork in Abram, TXFarm-era homes near the Abram levee often regain airflow from duct repair plus a condenser change.
- Ductwork in Las Lomas, TXA torn return in a Las Lomas attic pulls caliche dust into the air handler.
- Ductwork in South Alamo, TXHumid air sweats on bare ducts in low, older South Alamo homes and stains ceilings.
- Ductwork in Roma, TXThick masonry in Roma's historic district leaves few duct routes, so ductless may fit better.