Questions on way to insulate bare metal, between where the flex stops (on an El), and up to the collar at plenum?
Flex comes from the R - to the 90 El; flex insulation covers several inches - of one end of the El.
Collar / plenum is to the L.
Have foil back duct insulation - can use to wrap remaining bare part of El & plenum collar.
* At * the collar (using loose duct wrap), should the insulation be zipped - only - to the collar? Or taped to collar, then zipped?
On this El, should the end of flex's insulation be zipped against the El,
then overlap the duct wrap - several inches ? past the end of flex insulation?
Last, should the joint where duct wrap OVERLAPS the flex insulation be taped / sealed to the flex's outer covering (shiny, mylar / plastic type shell)?
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