I have a split system located in my crawl space. The vents consist of one main large metal tube with insulation on it. The branckes to the floor registers are flex. Over the years I have had cats and animals get under there and tear the flex.

Is it better to go all metal ducts? Can I wrap regular insulation around them?

Is there a sleeve or some other protective thing like pipe insulation I could use over the current branches?

I appreciate it!

writes:

I have a split system located in my crawl space. The vents consist of
one main large metal tube with insulation on it. The branckes to the
floor registers are flex. Over the years I have had cats and animals
get under there and tear the flex.

Is it better to go all metal ducts? Can I wrap regular insulation
around them?

Is there a sleeve or some other protective thing like pipe insulation
I could use over the current branches?

Duct tape!

--
Dan Espen

The straighter and smoother any airway is, the less resistance to air flow it will offer and the better the air flow through it will be. So, for any kind of duct, whether it be a dryer, ceiling fan or building HVAC ducts, you get the best air flow with smooth rigid sheet metal ducting. And, if it's an option, consider going to a larger diameter duct to further reduce air flow resistance.

Look in your yellow pages under "Heating & Cooling". Any HVAC contractor in your area will know who sells "All Service Jacket" pipe insulation. This is a resinous fiberglass pipe insulation that can be applied on any kind of piping to reduce heat loss or heat gain.



ASJ comes in 4 foot lengths (that I know of) and in a wide array of ID and wall thicknesses.

If you're willing to pay extra, you can buy 90 degree corners in ASJ as well, but most places wouldn't stock them. You'd have to order them in. Most people just cut the ASJ at a 45 degree angle (and possibly trim the insulation on the inside with a pipe shooter for a nice fit on pipe elbows).

Here's a "pipe shooter" that you can use to trim the ASJ to fit over changes in the OD of the ducting. You probably won't have any, but on smaller diameter water heating pipes you'd have all kinds of elbows and unions to cover. The pipe shooter is fitted in an electric drill:

On 4/22/2013 6:29 AM, wrote:
I have a split system located in my crawl space. The vents consist of one main large metal tube with insulation on it. The branckes to the floor registers are flex. Over the years I have had cats and animals get under there and tear the flex.

Is it better to go all metal ducts? Can I wrap regular insulation around them?

Is there a sleeve or some other protective thing like pipe insulation I could use over the current branches?

I appreciate it!
Have a local heating/cooling contractor replace the flex with solid
metal with insulation. You will only have to do it onc

Paul