Is ANYTHING a DYI project?

[cissado]

I may want my flex ducts and metal trunk line insulated in my attic. Can this be a dyi project or should I get a pro to do it? I've recently had a lot of work done on the two units up there, but I doubt my installer would even want that job.

Can I really mess it up that badly? All the flex in the attic is fairly accessible and there is about an inch of insulation on the metal duct which I THINK is ductboard inside as well. The flex is a combo of the silver colored type and some black colored flex.


Before anyone gets upset. I know this isn't a dyi site and I have learned that most work is better left to the pros. That's why I hired my installer, but this may be different.


I would like to hear opinions to help make my decision.

[citywide service]

If the main metal duct is insulated inside the duct I am not sure your gonna gain enough to warrant the cost of the insulation.

As far as the flex is concerned...the silver flex is rated at R-6, the dark grey is R-4, make sure the "black" flex has insulation on it, if you can see the wire on the duct inside then it needs attention.

I had a house where I ran all the duct in flex off a plennum and then insulated the hose with R-38 in the attic and covered the runs with insulation (I didn't the insulation contractor did) and that seemed to work ok I guess; not sure if it was the ducts being coverd or the R38 but would put my money on the R-38, you might try that instead.

Insulating flex with ductwrap will be a pain and you probably wont gain enough to talk about...Why do you want to do this, what is your reasoning?


CW.

[mini-split-dude]

What is dyi ????

[citywide service]

"do it yourself"

[mini-split-dude]

[nina]

mini-split-dude wrote:
>What is dyi ????

do yell impossible

[cissado]

LOL Sorry, I meant diy.


My "reasoning" behind insulating is the units are in the attic and the temp swings are pretty drastic up there. I've recently noticed some sweating on some rigid ducts where the insulation was loose and not covering the duct. That gave me the idea of maybe doing the whole thing. Plus the black flexis not a high R-value, so I'm sure it would help in the winter time at least.

I have a controller to run the blower 24/7 at low speeds and I seem to feel it when the temps in the attic are extreme and there's no call for heat or cool. I figured insulating would level the playing field a bit more, so to speak.


dyi = "do yourself (an) injustice" You pros may like that.

[citywide service]

You would be better off and get cheaper utility bills if you use a gable vent with a humidistat in the attic, this controls the temps better in the summer and humididy in the winter.

The R values on the flex is really fine, been using that stuff for years in the trade and no real problems as long as the insulation surrounding the duct is in good shape.

Spend your money on the gable vent and watch your utility bills go down.


CW.

[hvac hero]

I see nothing wrong with a homeowner insulating existing duct up in the attic. A lot of times a handy homeowner can spend more time on a project like this & go to greater pains to have a really neat job than some companies he could find to come in & knock it out in a day. I cant believe someone would put a system in for you & have a uninsulated metal trunk line in your attic.

If I were you, I would turn the fan on & go through all the square duct & check for leaks & seal em up with pooky or silicone before wrapping the duct.

Good Luck.

[keepitsimplestupid]

"dyi" - "do yourself instructional" site