Water bottle, food, and electronics cold weather insulation bags. Lets DIY together.

[Kittyslayer]

Remember that whatever insulation you choose is only going to maintain the items current temperature a bit longer. It will not be generating any heatto keep it from freezing if it is already near 32f.

Water bottle - the 40f water you got from the creek will only stay at 40f if insulated and will start to drop from there depending on the outdoor temperature and amount of insulation.

Filter (the one you are not supposed to let freeze) - after filtering 40f creek water the filter elements are going to be 40f. If you put the filter in a Ziploc and next to your body you can raise its temperature with body heat. It will warm faster without any insulation blocking your body heat from warming the filter. Once warmed by your body insulation will help maintain that temperature but for how long? Tucking it in the foot of your sleeping bag without insulation will allow your body heat to keep it from freezing.

Food - whatever temperature your backpack was when you got done for the day and hung your bear bag is the starting temperature when you insulate it. When you wake up in the morning you could retrieve your bear bag and put whatever energy bar you plan to eat for breakfast in a pocket to warm it enough so you don't break your teeth.

Electronics - once again whatever temperature they are while carrying is what temperature they will be when you tuck them in the insulation. Your body heat (and stove) are the only heat sources you have.

Batteries - (do your own research) - I read, but don't recall where, that your battery is okay being cold as long as you are not using the battery. So the theory is if you let your battery get cold wait to use (recharge) your phone, etc. until the battery has been warmed back up.

[VeganHiker]

Rockywoods returned my inquiry. Splitting half a sheet will yield aboutt a 21x47 for each of us. That will be enough for a few bottles or whatever you are using it for. That will be about $ 25 US plus shipping for your piece for anyone that wants it. Paypal, cash or cashapp. PM me. Here is the link again. https://rockywoods.com/products/3-0m...bfed4c25&_ss=r

[Daybreak]

I have DIY experience with the 3 JoAnn's materials. The reflective value for a shiny metallic fabric is not disputed for retention of heat. Columbia has used it successfully.

Note the Colombia brand on the reflective foil (or maybe fabric) of the recent moon lander.

https://www.scientificamerican.com/a...lunar-surface/

[Montana Mac]

For my freezer bag cooking cozy I just used craft foam that I bought at Wal-Mart and super glued my seams together. It has held up for 15 years without separating. It should be easy enough to fabricate a water bottle cozy out of the same material.

[Odd Man Out]

I diy pot cozies using silver mylar film coated foam from car windshield sunscreens. Cut with scissors and tape with aluminum tape. It's thin but can be doubled up if you want it thicker.

[BobTheBuilder]

I was wondering when somebody was going to point this out. Insulation keeps your body warm because you generate your own heat and the insulation slows how quickly that heat is lost to the environment. Your food, water, and electronics just sit there quietly, not generating their own heat.

[Alligator]

I was wondering when somebody was going to point this out. Insulation keeps your body warm because you generate your own heat and the insulation slows how quickly that heat is lost to the environment. Your food, water, and electronics just sit there quietly, not generating their own heat.

Yes, no, and maybe. Yes food is just sitting there for the duration in the pack. I see that is in the title but I wouldn't see a need for food insulation constantly. A cozy is very beneficial for rehydrating food or freezer bag cooking. Clothing can serve there too if you wanted. I prefer a pot cozy as it helps minimize spills while waiting. Water in the winter often needs to be heated. In it's liquid state it is going to lose heat if the ambient air temperature is below freezing. Electronics generate heat with use, with use being as simple as on. How much is probably not too significant. Cold does impact batteries but I'm not so familiar with various types to say how significant that may be.

Infrared temperature guns have gotten to be inexpensive and are pretty lightweight. Might be useful some time to bring one out to see how things perform in the field. Even the backyard would work.

[Patrickjd9]

Electronics - once again whatever temperature they are while carrying is what temperature they will be when you tuck them in the insulation. Your body heat (and stove) are the only heat sources you have.
Batteries - (do your own research) - I read, but don't recall where, that your battery is okay being cold as long as you are not using the battery. So the theory is if you let your battery get cold wait to use (recharge) your phone, etc. until the battery has been warmed back up.

Another issue with small electronics is that they have almost no thermal mass, so there isn't much heat to retain with insulation. It is probably best to protect them from extreme cold with padding/insulation, especially since cold objects are more likely to break if dropped.

A better option may be to put them in a pocket or inside a jacket before using them in the morning. The same idea goes for keeping them in your sleeping bag if you will be using them during the night, such as for listening to music or a podcast.