Ductwork design & repair
Your System Is Only as Good as Its Ducts
The best furnace on earth can't fix a duct system that leaks a third of its air into the basement. We design, fabricate, repair, and seal ductwork that actually delivers.
Sheet metal & airflow
Most comfort complaints are duct problems wearing a disguise.
The bedroom that never cools. The whistle when the system kicks on. The dust that's back two days after cleaning. Homeowners blame the furnace or the AC — but in a huge share of cases, the equipment is fine and the ductwork is the culprit: undersized trunks, crushed flex runs, disconnected joints, and leaks that dump conditioned air where nobody lives.
AJM does real sheet-metal work — designing, fabricating, and installing duct systems, not just taping what's there. That matters in Philadelphia housing, where decades of renovations leave behind duct paths that were never engineered for the equipment now attached to them.
Typical duct systems leak 20-30% of their air. Sealing and correcting that is often the highest-return HVAC money a homeowner can spend — comfort improves room by room and the same equipment suddenly performs like it was always supposed to.
What's included
Ductwork, done as a trade
Custom sheet-metal work sized from airflow calculations — not guessed from what fit last time.
Crushed, disconnected, and rotted runs rebuilt so air arrives where it's supposed to.
Joints sealed system-wide — reclaiming the 20-30% of air most systems leak.
Dampers set room by room so the far bedroom gets its share, finally.
New furnace or AC? We correct the duct side so the upgrade actually performs.
Duct extensions engineered for new space — not a flex run stabbed into the nearest trunk.
Know the warning signs
Six signs your ducts are the problem
If the equipment runs but the room stays wrong, the air isn't getting there.
Whistles are leaks; rumbles and booms are undersized or unsupported duct flexing.
Leaky return ducts vacuum dust from attics and basements straight into your air.
Paying to condition air that leaks into crawlspaces shows up every month.
Barely a breeze at the register means restriction, leakage, or bad design upstream.
Door-juggling to steer comfort means the system was never balanced.
Noticing one or more of these? Request service before a small issue becomes a replacement.
How it works
How a duct project works
- 1Inspect & measure
We walk the whole duct path, measure real airflow at every register, and find the losses.
- 2Engineer the fix
A scoped plan — seal, repair, rebuild, or redesign — priced upfront, worst problems first.
- 3Fabricate & install
Sheet metal cut and fitted to your home. Clean workmanship you can see.
- 4Measure again & balance
Airflow re-measured at every register to prove the difference, then balanced room by room.
Common questions
Custom Ductwork FAQs
How do I know if my ducts leak?
The tell-tale signs: rooms that won't condition, dusty air, weak registers, and bills that outrun your equipment's age. We measure actual airflow at every register and find where it's going.
Is duct sealing worth it on an older system?
Often it's the best money you can spend — sealing costs a fraction of new equipment and frequently delivers a bigger comfort change. It also means any future equipment you buy performs to spec from day one.
Can you add a return to a stuffy room?
Yes — missing returns are epidemic in older Philly homes, especially upstairs. Adding one is routine work for us and transforms rooms that always felt pressurized and stale.
Do you do commercial sheet metal work?
Yes — fabrication and installation for light commercial spaces as well. Call with the specifics and we'll scope it.
Request service
Ready when you are.
Tell us what's going on with your ductwork and we'll get back to you fast — usually the same day. Prefer to talk? Call (215) 271-0682 any time, day or night.