View Full Version : Average cost of new duct work?

Miriam Barton
06-03-2007, 09:29 PM
Thank you all for your responses to the rust in the duct work.

Any one know the average cost of filling in the old duct work in the floor and running new duct work through the attic? How pricey could it be? $2,500 or $10,000

The house is 2400 sq ft. and assuming the old duct work would be sealed in with concrete does that make it more?

I'm assuming any HVAC company could be contacted to have this done, correct?

So appreciate the help.:o

Phillip Stojanik
06-04-2007, 12:00 AM
The price could vary quite a bit depending on where you live. As far as installing a new duct system in the attic goes, I think you would be in the ball park if you counted the number of supply ducts you needed and multiplied by $225

For example, if you need 12 supply drops total, that would be 12X$225=$2,700 Do you also need to relocate equipment into the attic? If so, that will run the cost up considerably.

Filling in the abandoned underground ductwork is a separate issue and you may need a different kind of contractor for that although you might find an HVAC company who is willing to do it.

Rather than cement you may consider have the passages filled with a two part expanding foam and then just capping them off with a 4-6 inch cement plug. A general contractor might be better suited for this kind of work.

Richard Rushing
06-04-2007, 06:39 AM

Just saw this thread... I posted on the other one as well.

I looked the pricing up on Xactimate 24 (estimating software--city specific) and confirmed that Philip's pricing is VERY close and in-deed could be used as a general rule of thumb (there will be extras to be added to the cost).


Jerry Peck
06-04-2007, 12:44 PM
One major factor not being factored in to the above costs is "accessibility"

Trying to calculate based on $225 time the number of supplies does not take into consideration that, for a two story home, *how* do you replace those for the first floor, *how* to you get to the ducts where there is no room, *how* do replace the ducts which are snaked in and around trusses, *how* ... you get the idea.