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0% for 25 months on a qualifying new Rheem® heating or cooling system. Installed by November 15.
INSTALLATION STANDARDS · METAL DUCTWORK
How Honest Fix Fabricates and Hangs Metal Duct
Metal ductwork is the trunk of your whole system, the main line every room branches off. Built well, it moves air quietly and loses almost none of it. Built fast, it leaks conditioned air into your basement, drums and pops when the blower kicks on, and sags where it should run straight. Honest Fix fabricates and hangs every piece to a written standard: straight, quiet, and sealed where a leak actually costs you. This page is that standard, published in full, so you can hold any contractor to it. Ours included.
Published from our Installation Handbook · Reviewed by Alex Largent · 100% satisfaction, no exceptions
Sealed Where a Leak Costs You
Every connection at the equipment is sealed on every job, and duct running through an unconditioned basement, crawlspace, or attic gets its seams sealed too, because that is where a leak is air you paid for and will never feel.
Hung Straight, Hung Quiet
Trunk lines hang level to the joists on proper straps, with a gap that keeps the metal from drumming and popping as it heats, cools, and pressurizes.
Cross-Broken So It Does Not Oil-Can
Flat duct faces are cross-broken to stiffen the metal, which stops the booming oil-can pop you hear when a weak duct flexes under blower pressure.
How it hangs
Trunk lines are hung straight, level, and plumb on proper metal straps and hangers, at least four inches off a crawlspace floor. There is a deliberate gap at the joists so the metal is not transmitting noise into the framing: supply trunks hang one inch down from the floor joists, return trunks hang tight to them. Runs are hung leaving room for the required insulation, and spaced so expansion does not make them tick and pop.
How it seals, and where
Sealing is not decoration, so Honest Fix puts it where it changes what you pay. Every connection at the equipment is sealed on every job: the plenum, the transitions, the filter cabinet, and the starting collars, which get silicone specifically because duct sealant will not close the larger gap there, with the dovetails left flush inside the duct and screwed properly. Out on the duct runs, sealing follows the space the duct is in. A trunk crossing an unconditioned basement, crawlspace, or attic gets its seams, joints, elbows, end caps, and cleats sealed with duct sealant, metal tape, or silicone, because every leak there is conditioned air dumped into a space you do not live in. Where a sealant line on an exposed plenum will be painted, it is taped off first for a clean finish.
How it stays quiet
Flat duct faces are cross-broken in the proper direction to stiffen the metal. Without it, a wide flat face flexes when the blower pressurizes the duct and snaps back with a boom, the sound people call oil-canning. Screws are spaced evenly along the metal, both for appearance and to keep the panels from waving. Where sound liner is used, it is cut straight and tacked so it cannot blow loose into the airstream.
How it is finished
The details that separate a professional trunk from a fast one: manufacturer stickers are removed after fabrication, foil-backed insulation is the only pre-approved wrap at Honest Fix, and the whole run is left clean and square. Where metal duct meets flexible duct, that connection follows the flexible ductwork standard, and every run in an unconditioned space is insulated per the insulation standard.
Last Updated: November 12th, 2026
Have a Look at Yours
Now you know what correct metal ductwork looks like. If yours sags, leaks, or bangs, or you would rather have someone else check, Honest Fix will come out and give you a straight answer. No upsells, no games.
Flexible ductwork · Duct insulation · The full Installation Standard
