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Thread: bag warmth

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    bag warmth

    Got a hypothetical insulation question for you. Lets say I have a down bag, say 30 degree rated. It's a mummy bag and it has a thickness (when used as a mummy bag) of 2" of down on top of me. (this is hypothetical by the way).

    If I were to use the same bag as a quilt on top of me, would the down pile up differently because of the sides of the hammock making the layer thicker and increasing the thickness of down, thus the temperature rating?

    --Matt

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    Does the mummy bag have continuous baffles, ie, is there a seam separating the top of the bag from the bottom? Can the down migrate freely in the baffle from one side of the zipper to the other? A side seam would limit the effectiveness of shaking down into the middle of the "quilt."

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    Put simply, Yes. The down will be able to trap more air above you.

    Drafts around the head end are a worse problem though, as is dribbling on the hood.


    Please note:- I only dribble hypothetically.

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    Quote Originally Posted by turnerminator View Post
    Drafts around the head end are a worse problem though, as is dribbling on the hood.


    Please note:- I only dribble hypothetically.
    I don't play basketball. oh you said dribbling ON the hood.

    Aren't drafts around the head a problem with quilts too?

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    Quote Originally Posted by Mundele View Post
    I don't play basketball. oh you said dribbling ON the hood.


    Aren't drafts around the head a problem with quilts too?
    I would think so, but I only use a bag. My bag cost too much to leave at home, and it works great in the hammock as a quilt/ mouth mop.

    I go to ground sometimes and I think a bag is better for me on the ground.

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    more loft = more warmth

    but you would need the same loft in your UQ too

    not quite double the warmth but a lot, test it this Fall

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    Thermarest makes winter bag liners that have warmth ratings, for example a +8* liner, or a +25* liner. This increases, in theory, the rating of your sleeping bag. So, it you wanted to use the bad as a top quilt, you could, theoretically, get inside the bag liner for the first layer of warmth, and then use the opened bag on top for more.

    Sounds good, anyway. Who knows? I have one rated +8* - 10*. Haven't needed it yet.
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    I've used my 40*F down bag as a quilt into the upper 20*F and it worked great. Of course I had a Mt Wash 4 underquilt too.

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    I have successfully used a Mountain Hardwear 25/40F sleeping bag (one half is rated to 25, the other 40) down to 7F multiple times. I am a warm sleeper, and I was perfectly fine. I never wear anything more than shorts and a t-shirt to sleep.
    IMHO, if you have enough insulation under you, you can skimp on the TQ.

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    Quote Originally Posted by Mundele View Post
    Got a hypothetical insulation question for you. Lets say I have a down bag, say 30 degree rated. It's a mummy bag and it has a thickness (when used as a mummy bag) of 2" of down on top of me. (this is hypothetical by the way).

    If I were to use the same bag as a quilt on top of me, would the down pile up differently because of the sides of the hammock making the layer thicker and increasing the thickness of down, thus the temperature rating?

    --Matt
    with your hypothetical situation you'd still need to test it out!! And most sleeping bags have a divider or way of keeping the insulation that's ment for the bottom, to stay on the bottom. Meaning that you can't shake more insulation into the top part of your bag. One other thing you'll need to look at is that 30 degree rating of the bag. That's usually just a ballpark figure for you to go by. I'm a cold sleeper and I remember once sleeping (on the ground) in a 15 degree bag and being extreamly cold in only 34 degree weather. Now in my hammock I can take that same 15 degree bag and use as a top quilt and stay warm and toasty down to about 30 degrees. The difference is that I've now got a 5 degree quilt under me (hanging under my hammock). Again remember that I'm a cold sleeper. I've since made myself a winter top quilt, rated around 5 degrees and it's kept me warm and toasty down to 20 degrees (windy, snowing!!)

    Hypothetical is only good on paper. Once you get out and start testing out your gear, you'll find what works and doesn't for you. Like these ratings on sleeping bags. I have to add/subtract about 15 degrees to even be in the ballpark for what works for me.

    TinaLouise

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