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Billbill84

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IMG_0779.JPG IMG_0780.JPG IMG_0781.JPG IMG_0782.JPG IMG_0785.JPG IMG_0786.JPG IMG_0787.JPG IMG_0788.JPG IMG_0790.PNG IMG_0792.PNG Hi all. So like every DIY guy out there we all know every house is an animal in itself, meaning, you gotta learn how all the systems are setup, what makes it tick, and what not to mess with.
Here's some info: house built 2001. Fully finished 1300 sqft basement with sheet rock walls and ceilings. In summer basement is coldest place and winter, luckily it's the warmest by far. Furnace unit is also in basement.
My furnace struggles to get conditioned air hot or cool, all the way up to the 2nd floor upstairs. First main floor is always comfortable and in winter main floor is great and floors can fool you as being heated....keep this detail in mind for later.
So this past summer instead of messing with individual supply registers, my trunks off the air handler have dampers on each trunk. I slightly backed off the supply dampers to force more cool air up to 2nd floor. It worked good enough and all was good. Now the cold weather is coming and while I was in basement going to valve off the outside hose bibs, while peeking up in ceiling around rim joist I noticed a LOT of exposed rim joist with very little insulation and what's even there is yellow R13 I believe. I'm wondering how the heck these pipes never froze and burst?!? Then I got to thinking....while all the duct work is hidden up in the drywall ceiling, it's uninsulated ductwork which means there's probably a decent amount of leaks which would be heating the area ceiling cavity up to the rim joist area which would also explain why no pipes ever burst up there.
When i first moved in they had them dampers fully open which, if my theory is correct, would protect that ceiling cavity with warm air from leaks and if it's doing that then the rim joist and pipes would be benefiting from the warm air leakage and there's a lot of copper pipes in my rim areas!
Conclusion, It's been cooler out last few nights and was wanting the 2nd floor a little warmer again for the kids, but then thought with the outside temps dropping maybe I should open the trunk dampers fully (like they were when we moved in), to let that warm air concentrate around inside the basement ceiling/rim joist area to avoid disaster. Opening the dampers weakens the flow going up to the 2nd floor rooms obviously, remember it worked in summer for cool air but maybe not a good idea in winter?
For now after I shut off hose bibs I carefully stuffed some unfaced R30 on the backside of the water lines and valves against the rim. Is this ok?
Any thoughts on this are greatly appreciated guys please chime in. Thx. (Pics below & red circles are the dummy vents for outside winterize shut-offs and other pics are my furnace with directional arrows and dampers. Thx
 
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IMG_0793.PNG Oh here's another pic of the opposite side of basement inside shut off valve hole. Has more insulation then other side thoughts
 
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It’s very common to have different damper positions for heating season and cooling season.

Open them all up to how it was when you got it (after marking your cooling season positions so you know where to set them again next year) only close of as much as you need. Too little airflow will damage your furnace heat exchanger.

Insulation around pipes never hurts. If it gets hot in those areas it may be worth putting proper foam insulation in them so it has a vapor barrier also.
 
Supply ducting is generally insulated on the inside, although, depending upon the age of the installation, they are later wrapped.

It ia also common for people to place insulation behind the return air grates, which can reduce flow.
 
Supply ducting is generally insulated on the inside, although, depending upon the age of the installation, they are later wrapped.

It ia also common for people to place insulation behind the return air grates, which can reduce flow.

The insulation on the inside of ducts is for acoustic purposes only and provide no thermal insulation at all. The outer wrap insulation provides the thermal and vapor barrier but that is only required when the ducts are exposed to unconditioned spaces or untempered air.

I thought the OP was talking about insulating their water pipes though. I may have miss read the post.
 
The insulation on the inside of ducts is for acoustic purposes only and provide no thermal insulation at all. The outer wrap insulation provides the thermal and vapor barrier but that is only required when the ducts are exposed to unconditioned spaces or untempered air.

I thought the OP was talking about insulating their water pipes though. I may have miss read the post.
Yep you're right I was talking about water pipes, most of which I cannot get to. Zoom in on the pic of rim joist area and you'll see. There's no way to get to them as i had to stick my hand up there to get the pics and when I saw what the cam captured I was stunned to see a crappy insulation job which is all covered by drywall. As I said before, I think the only thing saving me was warm air leakage from ducts buried up in the ceiling/rim cavity and all this leaky air could also sort of explain why it's so cold on the 2nd floor and why people think we have heated floors when they come over lol. I think it kinda makes sense...
 
It ia also common for people to place insulation behind the return air grates, which can reduce flow.
There are no returns in basement them are dummy vents used to hide the hole that is the access point for my outside bib shut offs.
 
That is in part tru, however, there is "O" thermal loss by heating the metal ducting, which is then reradiated to the surrounding area, really?
 
The heated air passing thru the duct, heats the uninsulated duct, that heated duct then reradiates that heat to the surrounding area, ergo, heat loss.
 
The heated air passing thru the duct, heats the uninsulated duct, that heated duct then reradiates that heat to the surrounding area, ergo, heat loss.
Yes that and some leakage is what I'm thinking is happening and probably the only reason no pipes ever froze and broke because the drywall ceiling makes a nice little insulator pocket for any heated air to seep near the rim joist/copper lines thus not freezing, and would explain why my tile
upstairs feels warm, but unfortunately reducing efficiency to my 2nd floor upstairs.
 
That is in part tru, however, there is "O" thermal loss by heating the metal ducting, which is then reradiated to the surrounding area, really?

I’m not sure if you are referring to the insulation inside the duct. If you are then I will expand on that for clarity.

The internal insulation is better described as a porous blanket used to slow the velocity of the air as it come in contact with the duct. The air moves freely through it, just slower. It also adds mass to help dampen the high pitched ping of the duct down to a low and quieter drum sound. There is no thermal protection since the air moves through it while it travels through the duct and is therefore still scrubbing the metal and transferring heat.

External insulation on duct is designed different. It provides no significant acoustical dampening but provides a thermal barrier and a vapor barrier. The external insulation I’m talking about is the silver foil outside with fiberglass insulation that you see today.

In commercial applications you will often see their ducts insulated with both internal and external insulation, to meet the demands of their design specs.

If you are not referring to that then I apologize for the misunderstanding.


This thermal transfer that you are talking about is probably benefiting the homeowner (OP) quite a bit by keeping the space the pipes are in slightly warmer, along with the minuscule air leakage at the pipe joints in that space. It wouldn’t hurt to insulate the rim hoist if there is nothing there. Installing frost free hose bibs would be a good addition to any home in my opinion, just remember to let them drain come winter time (by removing anything attached to the hose bib). It does seem odd that there is no insulation installed there. It is probably a pretty cold area of the house during the winter time I’m guessing.
 
This thermal transfer that you are talking about is probably benefiting the homeowner (OP) quite a bit by keeping the space the pipes are in slightly warmer, along with the minuscule air leakage at the pipe joints in that space.
Yes exactly! And my entire issue of the 2nd floor being so hot in summer was remedied by cutting back on the two main trunk dampers pictured above to force more cool air straight up the round trunk to the 2nd floor above main floor. But now approaching winter, winterizing hose bibs I saw little insulation at the rim by all the copper and thought "how did this stuff never freeze? The warm furnace air needs to stay low near basement and main floor and the basement IS the warmest place in the whole house during the frigid cold winter. I need to open them dampers fully again and just have to deal with a cold upstairs and put thicker PJs on the kids come bed time I guess lol. Maybe when I have my new furnace put in I can have it installed in place of current unit, move old one aside and tie it in just to the round duct that feeds that cold 2nd floor?
 
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