Duct Board Vs Sheet Metal

When homeowners receive quotes from hvac contractors they typically are given two duct replacement options sheet metal or fiberglass duct board.

Duct board vs sheet metal.

Flexible ducts are good for air quality because you are not breathing in fiberglass insulation lined ductwork like the fiber air ducts and they are mold and rust resistant unlike galvanized sheet metal ductwork. The porous surface seems like it would affect air flow i understand properly sized this shouldn t be a problem collect more dirt than metal delaminate and come apart over time and are very hard to clean once dirty. And then that goes up maybe i don t know a foot and a half 2 feet. It is not rodent proof.

I just don t know what that is. If you re going this far perform a flowhood test to determine where how much improved airflow can be had. You need a pro for this. While flex ducts work best for short runs in a trunk and branch system metal duct works best for entire air distribution systems.

Duct board vs metal plenums supply is on perferable over the other. 25 feet should it be ductboard or metal and is hard pipe runs preferable over flex. Poor fastened and sealed connections. Coat seal the interior of the duct board using an airless sprayer.

Odds are the efficiency airflow of your duct system can be greatly improved. Metal ductwork needs design measurement and installation by or with the help of an hvac professional. If i am going to have a supply plenum run for approx. Generally airflow is better with metal ducting after a couple of years typically because of the dust and.

I don t know what kind of cardboard and i m sure there s a name for it. High air velocity will destroy the fiberglass material. Proper aspect ratio for velocity and pressure drop is more important than sheet metal. Up from the furnace comes a metal ducting duct work that goes up.

There is a third option phenolic duct that is made of plastic foam with a foil liner on the inside and exterior. The inner liner ribs restrict airflow more than sheet metal ductwork but not significantly. There actually are a few reasons most hvac techs prefer metal ducting. Replace redesign the duct board with sheet metal.

Duct board is ok if the system design is correct and the duct and fittings are properly made and installed. And then beyond that it s the ductwork is made of cardboard. I have never liked duct board or ducts lined with fiberglass.