Before insulating your ducts that run thru the crawl space you will want to
seal them first -- duct mastic is considered best though I've used the foil
tape to seal all the seams. I've used foil tape that has held up very well
over ten years now. Don't use regular duct tape -- it doesn't last. Seal
the seams of the heating ducts as well as the return air ducts.

I've used the fiberglass duct insulation by Manville that I picked up at
Lowes.

After sealing my ducts in my crawl space and then insulating all the heating
and air return ducts I noticed a big improvement in the air flow and the
heat of the air from the registers as far as how much there are a lot of
SWAG methods that others have talked about but I do know I'm saving now for
the life of the house and since I did the work myself my only costs were
materials and time.


"sherwindu" wrote in message
...
I am in the process of wrapping the forced air heating ducts in my crawl
space with
a material that looks like bubblewrap with foil on both sides. Does
anyone have any
idea of how much savings this will be on my gas bill? The insullation
is rated at R6, but I cannot relate this to actual savings in energy.