uninsulated ducts

[farseer]

Hi, most of the duct work in my basement comprises of what looks like a flexible silver insulation which wraps a pink fiber like insulation which wraps a black plastic like coil. I noticed that in one place in my basement, for about 5-6 feet or so, the duct work has no insulation, just the black plastic is showing. is this a big problem? Does it cause the overal system to be less efficient?

Also, if i wanted to replace a duct myself, can someone recommend a resource for reading up on installing ducts and what i would need to do so? I understand special consideration has to be made regarding the size of the opening used at the unit self that sources the airflow to the ducts. is this correct?

lots of question i know...but i have had such a problem with contractors when it comes to this system, i'd like to just finish it myself if i can.

thanks

[Smarty]

I've wondered about the logic of this. Even though the exit temp of the duct is higher after a duct is insulated, isn't the heat given off by an uninsulated duct going to eventually rise to the living space above and not be wasted? And isn't the space above the 25 foot run getting a more uniform temperature rise rather than delivering hot air at the very end of the run?

I recognize that ducts running in attics, unheated spaces, etc. are a different story and this theory does not apply.

Smarty

[Todd H.]

You had me up until you said coil?

Doesn't sound like a huge problem, especially considering that at least in my area, I haven't hardly seen a place around here that bothers insulating ductwork in conditioned spaces like basements.

You can buy duct wrap to patch up that area. The metal duct itself is intact right, just the insulation is missing in a small part? You can get rolls of duct wrap (insulation) at bigger building supply places.

Personaly, I just insulated a 25' run of duct work that was in an unconditioned crawl space under a first floor room that was there for

15 years without insulation. I'm in Chicagoland. The exit temperature of the registers on the end of that baby is sure a lot better now.

Best Regards,

-- Todd H.

[farseer]

Hi Todd,

What do you mean by the questi> "farseer" writes:

that at

[Edwin Pawlowski]

Mostly correct. Some heat may be lost other ways, but if you want to add heating or cooling to the room the duct is passing through, insulation is a waste.