Custom Duct Plenums Made to Order — Any Furnace or Air Handler
Yes. A plenum is the box that mounts to the furnace or air-handler outlet and feeds the trunk lines, and its dimensions are dictated by the equipment collar and the space around it — almost never a stock size. Enter the width, depth and height you need, and it's fabricated to fit that equipment and cavity, cut clean and formed square so the trunk take-offs seal.
The plenum sets up the whole system
Everything downstream connects to the plenum: the equipment on one end, the supply or return trunks on the other. If the plenum is the wrong size or out of square, every take-off after it fights to seal. It's the one box worth getting exactly right.
A made-to-order plenum is cut and formed to your measured dimensions so it drops onto the equipment collar and presents square, flat sides for the trunk connections.
What to specify
- Width × depth — the plenum footprint, set by the equipment and cavity
- Height — how tall the box is, set by available headroom
- Equipment opening — the collar size it mounts to
- Gauge and material — heavier gauge (typically 24–20) for a rigid box
- Connection type — slip/drive or flanged edges for the trunk take-offs
Supply plenums and return plenums are ordered the same way; returns are usually larger and lower-pressure.
Square and rigid beats field-bent
A plenum knocked together in the field from flat stock is only as square as the day allowed. A CNC-cut plenum arrives with clean, straight bend lines, so the box is actually square and the sheet metal is rigid enough not to oil-can under the blower. That squareness is what lets the trunk connections and any drop-in take-offs seal without a fight.
Configure Your Plenum
Size the box to your equipment and cavity, get instant pricing, and ship it to the job.
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