Good idea, but it decreases air flow due to the ribbed construction of the liner. It would be a cheap fix and more applicable to some of my favorite places....crawl spaces and attics! If you do choose to go that route, pull it as tight as you can. But...… heres the good part. You can still use the insulated flexible duct; that is, we would remove the interior plastic liner (with the metal ribbing) and then slide the insulation over the hard pipe. So, If your supply air run is 6", which is most typical, you would buy the insulated flex duct and then slide the outer portion of it (insulation with plastic or foil wrap) over the pipe. It's a bit of a challenge at times but the gain from it would help. Especially if there is no insulation in the joist space where the heat run is.
That area doesn't need to be vented. They just used those materials because they are [relatively] cheap and match the soffits that do need to be vented. Purely aesthetics. I would take the soffit material down, fill the cavities with solid foam using whatever materials will maximize air sealing, then put the soffit material back up. These uninsulated and poorly insulated overhangs are common on raised ranches or many house that overhangs the foundation or floor below it a little bit. I wouldn't move the heat duct, just foam around it, fully encapsulating it and maximizing insulation in the bay around it. The bottom of the pipe might be just R5 for a bit but that's better than the R zero or worse factor you have now.
This picture bothers me: Is there no ceiling there or did you just do a most excellent job of removing it ? Is there no insulation between the ceiling and the floor above the unheated garage ? That room must be ice cold in the Winter if there is none.
That's the same thing I thought when I first saw the pic. I was wondering just how couldn't he tell the bedroom wall wasn't extended out past the garage doors? But here is a pic with the ceiling still intact.
Yes it had a ceiling and while I'd like to take credit for doing a nice job of removing it, it was a pretty easy/clean removal of that exact section I needed access to because that's where joint ended, I lucked out big time. You can tell better in this picture! Yes, there was insulation in there and running in all the joist bays under the bedroom. Its double faced r-11 fiberglass. It was kinda of shoved loosely up in there, I don't think it was or is helping much but its there. Ice cold in the winter, which lead to this whole adventure. Trying to make it a bit more comfortable without going hog wild. Right thing is to pull it all down and re-do but budget constraints at the moment and like 5 other projects on tap. At least if I can stop that air flow from vented soffit will hopefully make a bit of difference.
I really should have known or at least took the time to stand on the side of the house and notice it does bump out a bit, not much but enough to see/know bedroom extended out.
Where the fiberglass insulation has turned black is where the fiberglass insulation was acting as a filter trapping the dust and dirt in the wind as it went whistling thru. Laying up solid foam panels in those bays outside is actually a pretty easy job. Best would be the spray foam but that's a rather small job to hire out. Solid foam, a little spray can foam to hold them in place and fill the gaps and you'll fix those ice cold floors in the room above. Nice weekend project. I wouldn't be surprised if the room on the back of the house had cold floors too. That's a HUGE heat suck.
That’s a garrison style cantilever. No reason to not encapsulate it that I can see- the builders just use the same soffit vent to keep exterior aesthetics the same
So our MA bedroom is on the back side of the house and while it can be cold it's nothing like my daughters. We don't have that vented soffit overhang on the back of the house like the front. Also the garage is 100% below my daughters room and only covers say 20 - 25% of our MA bedroom. There is actually a mud room, small hallway, and a powder room below our bedroom so we don't get quite as cold as her room. Also I suspect our HVAC vent does not go through the garage like hers but am not 100% certain of that. My sons room right next door has the same soffit setup, however there is no easy access to it like in the garage, I'd have to rip the ceiling down directly in front of the front door. Or perhaps there is a way to remove the soffit from outside. However his room is never as cold as hers is, I assume because the family room is below his bedroom not the garage like hers. I've been ripping 2" foam panels to fill the soffits in the front of the house below her bedroom and just picked up some spray foam to seal the edges. I also have some fiberglass insulation left over from an Attic project I will lay up against the foam boards. I agree it's really not a hard task, just need to find the time and extra $$ to do the entire garage. I maybe coming across more 2" foam boards from helping my bro in law, his sunroom ceiling is filled with it and we just demoed it last weekend and offered it to me. Awesome info from everyone, thanks again to all!
Depending on how those joists are supported by the main center beam, that cold air coming thru the overhang in the front could make it all the way to the back of the house. Joist pockets can problematic, especially the design that does not use a rim joist. That big leak on the front would be a lot worse if your joists were engineered open web joists. The whole first floor floors would be ice cold.
