"HeatMan" writes:
Well, SVL answered your questions..... And you are one cheap
(something-or-other).
Consider that many of my questions are about getting better quality,
not sure why you would get that impression...
There is a difference between not wanting to get ripped off and "cheap"


Why do you post your questions here? You say that you have had several HVAC
contractors look at it. They can see it and we can't.

Read on...

Well, contractors are in the business of "selling" you something. So,
when they see something that is not right, their tendency is to sell
you a new solution (not all, but many). I was hoping that I would get
a less biased opinion on this newsgroup.

Your answers though were *very* helpful. [SEE MY COMMENTS BELOW]


"Jeffrey J. Kosowsky" wrote in message
...
The previous homeowner did a DIY job of installing a new furnace using
a twisted maze of flex duct to make all the supply and return runs in
the basement.


That's one of the reasons the HVAC pro's don't like HO's to do their own
work.


Several heating contractors have advised us that flex is not intended
for long runs and that this is the most flex they have ever
seen. Also, there are no dampers and in some areas the flex is pinched
and the insulation tearing.


That's true. I don't much need for manual dampers around here, though

Well, the house is very old, uninsulated, and originally was designed
as gravity hot air. So my thought is that the system might need a fair
bit of manual balancing.



Couple of questions:
- Is replacing flex with rigid sheet metal duct work generally
worthwile?


I don't know. I would in *my* house. I don't have a lot of use for long
flex runs and won't warranty them on jobs the HO's or contractor asks for
it.


- Is it better to use custom sheet metal fabricated to fit tightly
between the joists or should we go with standard "round" ducts?


How much money do you want to spend? Custom metal can cost 1.5 times the
price of standard metal.
1.5x is not that bad, considering that materials is only a portion of
total cost, right?



More generally are there different qualities of sheet metal that
we should be concerned about?


You mean the gauge (thickness) of the metal? Most round duct around here is
28 or 30 gauge. Rect duct is usually 28 gauge, IIRC.

Would you recommend going for #28 over #30, if given choice?



- One contractor talked about "vinyl clad duct insulation". Is that
a good insulation solution?


Fiberglass duct wrap is on the way out and something has to replace it. The
vynil clad bubble wrap looks like the replacement, but it takes training to
do it correctly.

So, this is a good quality choice, right? Are there different grades
to be concerned about?



- What types of dampers should we be installing for best results?


Manual dampers? For air balance? If the ducting is done correctly, you
won't need dampers for balancing.


- Any other questions we should be asking regarding duct work?

Will you be getting a performance warranty? Will the duct work be sealed?
Can I get a contractors discount?

You should better read the thread on contractor's discount -- the
original question was about DIY projects not about jobs like this
where a contractor is used.