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New duct work, what to look for?

Posted by brad_hucks (My Page) on
Thu, Apr 19, 12 at 12:07

I'm getting my duct work repaired/replaced. Contractor coming out Monday to finalize the quote & paper work. I need to have a general sense of what I should be getting when having this work done. I know that all new flex should be R8. They are re-doing the plenhum and making it come off the blower in more of a Y shape. They are raising the existing unit off the floor (not sure why). They are putting in a bypass, they are adding an auto shut off, they are adding dampers to some of the supply lines to better control air flow. They are ensuring my 2 zones will work properly after install. They will be using mastik tape. What else should I ask for or require them to do? I've heard of a supply air sensor, do I need one?


Follow-Up Postings:

RE: New duct work, what to look for?

Sounds like they know what they ARE DOING. I would not stress it just monitor the work as it is being done.

RE: New duct work, what to look for?

this is that $4200 job?
is it a repair or a replacement?
some areas are better sealed with mastic
that comes in a bucket and is applied with
a brush. I generally have both on hand.
I would look for more specifics.
repair or replace?
if you have a trunk line and flex comming off of
the trunk then unless they externally insulate the
trunkline then it is still R4...
what do you currently have and what are the
if you keep your posts in one thread it is
easier for everyone to keep track.

best of luck

RE: New duct work, what to look for?

Yes, this is the $4200 job. It's a repair job but they are replacing a lot of stuff, mainly the plenhum and some trunk. Sorry for double posting, here's the original thread:

Problems are general cold/warm spots in the house. A bonus room above the attic which stays hot, and in the summer the system runs all day and can't keep up.

RE: New duct work, what to look for?

so did you look into the foaming of the roofline
vs the cost of the ductwork?

bouns rooms in attics are surrounded by
attic air. upsizing the ducts to this area
doesn't always improve the comfort.

best of luck

RE: New duct work, what to look for?

I was told just nailing up insulation board over the studs and existing insulation on knee walls and bonus room walls made a significant difference as long as it is 3/4" or thicker if spray foam insulation is out of budget. I also have seen barriers made to box allow extra blow in fiberglass or cellulose over the duct work.

Insulating the ductwork might not seem to make that large of a difference to total output temp but it will make it get to that temp much faster if the ductwork isn't the same temp as the attic.

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