Flex Duct Vs Sheet Metal Duct

You mentioned that you were considering re insulating your current metal duct work.

Flex duct vs sheet metal duct.

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. More than likely. While flex ducts work best for short runs in a trunk and branch system metal duct works best for entire air distribution systems.

While they tend not to last as long as sheet metal they are very cost effective. Flexible ducts are made out of corrugated plastic often wrapped in insulation. Alternatives to flex duct. Air flow in a steel duct tends to travel smoothly in a coil like motion.

Well if we re not going to use flex what s left. If any duct product should be banned it s duct board. While sheet metal ductwork tends to be a better long term choice flexible ductwork has the advantage of relatively low upfront cost and versatility. Sheet metal ducts are less likely to incur dangerous mold and growths because their surfaces are non porous and smooth.

Even when doing this the flex duct creates much more resistance. Rigid metal is installed then mastic is applied to air seal then insulation is applied on the outside so there is less chance of fibers getting into your air stream. Most often flex duct is used to reduce cost or in places where metal duct work will not fit. This is a great decision.

Flexible ducts are fairly easy to install and will often cost less than the rigid ductwork. Their shape and size also allows them to be installed in locations that would not accept full sized sheet metal ductwork. Air flow in a flex duct tends to tumble probably because of the rib like intrusion every inch or so. If i am going to have a supply plenum run for approx.

That leaves rigid sheet metal often called hard pipe. If your budget allows you may want to consider resealing your duct work with a mastic product. Flex must be oversized at least one duct size.