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what is the initial cost difference between flex and steel ducting?

maya01 | Posted in Energy, Heating & Insulation on September 9, 2014 11:08am

We had steel ducts that had moldy insulation on them. We had mold remediators come in and clean up the place and contacted hvac to do the ducts. They gave us a quote for the work then suggested sealing the ducts w/ mastic which we agreed to. Then he suggested getting all new ducts since everything would be down and said cost wouldn’t be much more. We jumped at that since everything was moldy and 30+ years old. Well 90% into the work I notice flex duct hanging. Turns out he gave us a mixed flex and steel system. We are going back and forth with them now since we never discussed flex. What is the price difference between the two 10,20,30%? Not sure where to go from here as they are not trying to honor their word and handwritten contract says the word “flex” scribbled. I want their sagging flex taken out. Has this happened to anyon?. We paid 6,000 for the mix how much do you think it would be to change all the way?

Thanks for any help. We just bought this home and it has been one thing after another.

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Replies

  1. mark122 | Sep 09, 2014 06:25pm | #1

    Duct work

    I guess this is a residential job you are refering to.

    With anything commercial you are only allowed to use flex at the tail end of each run (last 6')

    Flex vs. rigid duct pricing will vary depending on the part of the country you live in. I am in the south and rigid ducting in residential applications is always more expensive than flex. Honestly dont know what the $ comparison is for material, but labor is more.

    If you were to re use rigid ducting it would need to be re-insulated and sealed (mastic).

    If you missed the scribbled work flex when signing the contract your on your own...fighting a losing battle there. You should have a copy of what you signed so if its on that copy sadly you do not have a case. 

     Is there a particular reason why you are opposed to flex?

    Mark

    1. maya01 | Sep 09, 2014 07:22pm | #2

      This is in the se. I want the most energy effiencent system possible and everything I have read says sealed steel is the best. Besides they installed it improperly with sags and tight bends cutting off air. I know it stated on contract my husband signed not me,. but not once did they even even mention flex. I would not have gotten it at all if I knew it was flex. I don't know why they wouldn't have discussed the pros and cons of each since we had all steel ducts. Very bad business adn not honorable even if it is what was scribbled on the contract. Not a good way to do business.

      1. maya01 | Sep 09, 2014 07:24pm | #3

        I can't find price info anywhere. Everyone keeps saying it's more but won't say what percent more. My hvac people will not tell me either.

  2. mark122 | Sep 10, 2014 02:00pm | #4

    Who are you asking for pricing? I would be shocked if any contractor would tell you what their cost was on it...I dont tell my customers (in most cases) what I pay for materials, unless I am doing a cost plus contract. On small projects like this I offer a price for the contracted work. 

    I can understand your frustration if you assumed metal ducting, but I dont agree that its bad business on the HVAC contractors side if you have a signed contract. I would be upset at your husband not the contractor.

    If you are worried about air flow restriction on the bends, bring it up with the inspector (hope you are having your work inspected by your local inspectos). The city/county inspectors in your city/town will at least make sure that the minimum requirements are being met for a properly functioning system.

    In my experience, when a contractor knows he is not going to be inspected (by an inspector or G.C.) he is more likely to cut corners. Same would go for a contractor who knows he is doing work for a naive homeowner(not calling you naive in particular). Doesnt make it right, but i have found that to be true. That is why the concept of contracting licensed contractors, permits...etc is an important one.

    Sounds like you and the HVAC contractor may have rubbed eachother the wrong way, so I would, as cordially as you can, finalize the contracted work with the guy, retain a percentage (if allowed by the contract) until you can verify the installation was done properly and aproach the issue in those terms.

    Side note: duct work is hidden behind walls, in attics, or in basements/ crawl spaces so little attention is given to the aesthetics of the installation. Not sure what you mean by sagging duct work so just an observation.

    1. maya01 | Sep 10, 2014 02:37pm | #5

      oh believe me i am mad at him but when you have talked with a contractor several times and he changes your whole system to something new w/o even discussing it that is a problem. if you or anyone does business this way i would suggest changing. I did speak with him and asked what would've been the price to go with all steel originally. $1000!!! That's it. Why would I pay $6000 for cheap bottom of the line when I could get energy effecient,last forever sealed w/ mastic and insulated steel for $7000??? We are still working on a resolution. Again, if anything hopefully he will learn how to communicate with clients. Had plumber come today and he discussed a couple different options with me. That is good business!

    2. maya01 | Sep 10, 2014 08:34pm | #6

      my duct work is not hidden it is in garage on the ceiling and then it goes through crawlspace. Do you know what flex ducts are? Google it. They are supposed to be pulled tight and not sag more than 1/2 inch. I also was not asking what the price difference was just for materials but what they charge the client. I got the estimate from my worker. Too bad he didn't give it to me along with his flex price.

      1. maya01 | Sep 10, 2014 08:36pm | #7

        oh and thank you for the tip about a local inspector. def. going to do that.

        1. maya01 | Sep 20, 2014 01:51am | #8

          finally after a month we have came to an agreement and steel ducts are going back up. it would've been a $1000 difference but since they already put u flex and have to take down it will be $2000. Def. not a significant enough rice difference for me to get flex and save a couple dollars on something I feel will save us more $ in the long run and last forever. They will be sealed w/ mastic and wrapped w/ insulation. Yay!

  3. mark122 | Sep 20, 2014 09:16am | #9

    glad to hear

    Glad to hear you are satisfied with the re arrangement.

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