Duct Repair
Duct repair in Chattanooga, measured before it's fixed.
The rooms that never feel right usually aren't an equipment problem. They're a duct problem — leakage, restriction, or a system that was never sized for the house. We measure which one it is before anyone opens a wall.
The ducts are usually the problem
A residential air handler is built to run against about 0.50″ wc of resistance. Most of the duct systems we measure are well past that — sometimes double. When the ducts fight the equipment, airflow falls, capacity falls with it, the coil runs colder than it should, and the compressor runs hotter than it should. The thermostat has no way to tell you any of that.
So the complaints show up somewhere else: one room that stays eight degrees off the rest of the house, a system that short-cycles, air that never feels dry in August, a power bill that climbs while the equipment sits there looking fine. Homeowners get quoted a new system for all four. Frequently the equipment is the one part of the job that was done right.
How we find duct problems
We start with a static pressure profile — a manometer across the air handler, supply and return, which tells us in about a minute whether the duct system is choking the equipment and which side of it is doing the choking. Then the ALNOR balometer measures actual airflow at each register, room by room, so we can compare what a room is getting to what it needs.
Duct leakage testing puts a number on how much of the air you're paying to condition never reaches a room at all. Where it adds insight, an IR camera shows the runs that are uninsulated, disconnected, or dumping conditioned air into a crawlspace.
Every reading goes on your Home Comfort Report, along with what it costs you and what fixing it is worth. You see the numbers before you decide anything.
Sealing and repair
Most leakage lives in a handful of predictable places: the plenum connections at the air handler, the boots where a duct meets the floor or ceiling, the joints in old flex that was never strapped properly, and returns that were framed into a wall cavity and left to breathe whatever the wall breathes. Sealing those is mastic and hard work, not magic.
Crushed and kinked flex is its own category. A run that has been stepped on in an attic, or pinched around a joist, can lose most of its airflow without looking like anything is wrong. Those get repaired or replaced outright.
When the work is done we measure again — static pressure, airflow at the registers, leakage — and the before-and-after readings go in writing. That's the only honest way to show that a repair did what it was sold to do.
When repair isn't enough — redesign
Sealing a duct system that was undersized to begin with makes it tighter, not adequate. The most common finding by a wide margin is not enough return: one grille trying to feed a system that needs two or three, or a trunk that was sized for a smaller unit and never revisited when the equipment was replaced.
When that's the case we design the fix with Manual D rather than copying what was there. Trunk and branch sizing come from the room-by-room loads, the same Manual J numbers that drive equipment selection on a replacement — so the ducts and the equipment are finally solving the same problem. It costs more than sealing. It's also the difference between a system that limps and a system that works.
Insulation and condensation
Ducts running through a Tennessee crawlspace or an unconditioned attic live in weather. When the insulation has fallen off, compressed, or was never adequate, you pay to cool air that gives its cold back to the crawlspace before it reaches the room — and in humid weather the duct itself starts sweating.
Sweating ducts are a moisture problem with a real cost: wet insulation, stained ceilings, and exactly the conditions mold needs to take hold. The fix depends on where the moisture is actually coming from, which is a question worth measuring rather than assuming. Sometimes it's insulation. Sometimes it's a leak pulling humid crawlspace air into the system. We'll tell you which.
Common questions
Duct Repair questions, answered straight.
- What is duct leakage testing?
- A measurement of how much air your duct system loses before it reaches a room, expressed as a number instead of a guess. Paired with static pressure and room-by-room airflow, it tells us whether your problem is leakage, restriction, or sizing — three different problems with three different fixes.
- Do you clean ducts?
- Duct cleaning isn't what we sell, because it doesn't fix leakage, restriction, or undersized returns — the things that actually cause the complaints people call us about. We measure first and tell you what the readings call for. If cleaning is genuinely warranted, we'll say so.
- Can ducts be repaired without replacing the system?
- Usually, yes — and often it's the better order to do things in. Fixing airflow on equipment that still has years left in it can resolve the comfort complaint outright, and if replacement does come later, the new system gets installed into a duct system that can actually carry its air.
- How do I know whether to seal my ducts or replace them?
- Static pressure and airflow answer that. If the ducts are sized correctly and leaking, sealing fixes it. If the returns are undersized or the trunk was never right for the equipment, sealing makes a tight system that still can't move enough air — and Manual D redesign is the honest recommendation.
Where we work
Duct Repair across Greater Chattanooga.
Same measured process in Chattanooga and the towns around it. Find your area:
The standard
- Measured diagnostic on every visit
- Written report before any repair is approved
- Refrigerant recovered, weighed, and logged
- Owner-operated
Comfort Club members get priority dispatch and no trip fees.
Financing available on jobs over $500.