Brooklin wrote on 16 Jan 2005:

We have a few sections of flexible, metalized (but not metal)
ribbed tubing in the basement that connect the furnace to the
ducts going upstairs. This is probably slowing down a lot of
the airflow.

As the others have said, you really need a Manual D calculation,
with calculations for each run of duct. However. . .

My sense is that your ribbed duct isn't likely to be the major
source of the problem. While it will slow the airflow some, at
least it won't leak unless punctured. Metal rectangular duct, if
not properly sealed, which it wasn't until recently, will leak like
crazy, especially at every turn.

There are a ton of other factors that come into play, such as the
location of the thermostat - on the first floor, I'm guessing,
which would explain the lack of cooling in the summer on the second
floor.

I'd start with a consultation with a quality HVAC contractor who
can suggest various ways to fix the problems that are bothering
you.

--
Doug Boulter

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