The "shiny" quilted stuff, probably mylar with a mirror finish, should serve
as a radiant barrier and add to the efficiency.
Respectfully,
Ron Moore

"Kenneth" wrote in message
...


Howdy,

We have a geothermal water to air heating system with ducts
running through an unconditioned attic.

The ducts are not sealed, but they are (very modestly)
insulated with a shiny, "quilted" looking product to
something like R4.

We are soon to foam over these ducts, but...

There are two different approaches in the bids we have:

One wants to remove the quilted stuff, and then foam over
the bare metal of the ducts.

The other wants to foam over the existing insulating
material.

What would you suggest in this regard, and why?

Sincere thanks,
--
Kenneth

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