Using Rocks to Keep Warm and Stay Alive

You can also use a barbecue grill to heat the rocks, just make sure you place foil over the grill so no fumes get all over the rocks.

why not just get the rocks heating up in the sun?

If it's freezing outside they don't get hot.

okay build a solar oven and use it to heat up rocks. how about that?

Thank you for the tip.
Very wise. Will keep in mind.

Also, Aussie poster is right about using sun as heat.
Maybe we can let the rocks get hot while the sun is out and as soon as the sun is out put them in foil or something and put them in a metal bin or something?
Point is...we should think about how to extend the heat.
Thanks again for the good idea.

Caution is required when heating rocks!

Some rocks will explode!

I'm giving this suggestion to people who might find themselves in a bad situation, an emergency without power, etc. Not everyone is going to build a solar oven, but you can almost always have rocks and fire around.

Agreed, we heated them a good distance from us and only until we knew they were hot. We didn't let them sit there forever. Also, the kind of rocks in the pic are the ones that held up, other rocks just cracked apart.

great idea.how do you build a solar oven? please thank you.

Last Edited by now what on 11/20/2014 12:25 AM

You're very welcome! The night we had to use them in the tent, it actually got too hot inside, we had to open the tent door a bit.

do the rocks get sad or angry?
Why do they explode?

Good post OP

Thanks! I can't tell you how scared we were in the mountains when it got so cold so quickly. My friend got the idea and it worked unbelievably well. We spent the night in a cozy warm tent. We made sure the bucket was on top of rocks we found outside, so it wouldn't melt or burn the tent.

How do we place the rocks inside the tent and make sure we dont burn the tent our burn our skin?

Thanks for the tip, i could have used this when i was living in that abandoned house last winter.
Alas, its likely ill need it in the future.

Some say the rocks grow from gaia herself and that even when you sow the land to plant crop more stones and rock will appear because the rock be the seed of gaia.


Just some lore ive picked up in my travels.

Been there before on a hike. We had survival stuff, but we were only going up for the day. a cold front came in during the afternoon. On the way back, my hands started to freeze, and they were sweating earlier! Really scary how quickly the temps changed. I was already gameplanning on how we were going to survive if something happened. Made me rethink my hiking backpack.

Thanks for the great tip!

My friend always takes along a big shovel when we go camping. He just lifted the rocks into the bucket. Then we made several layers of rocks with air spaces to place the bucket on top of so the heat wouldn't directly radiate straight down to the tent.

Real Bricks may be a better Choice,
because they do not "explode by Anger"!

Here in Japan the rural People use/d Beans in a Sack for their Bed
but i do not know which one.

Sweating can be deadly if its cold. You have to be very careful and take a break or pull some layers off so you don't.

If we use our heads and get out of the "convenience" frame of mind, the earth provides many things that can save our lives.

Not everyone will be around bricks though.

You're right, but it wasnt the sweat and we had changes of clothes. It was the super quick temp drop. It was sobering to me how quickly it started to become a survival situation and we were doing everything right as far as I thought!

Rocks keeps me alive

One can heat any thing, be it sand or gravel in a bucket, clay soils. Even brick will work.

One wants to keep away from top soil as it will stink horribly, the organic material lets off lots of foul stuff. So if you don't have rocks but lots of soil, dig down at least 4 inches to get at the deeper soil that has much less organic matter.

And one may want to keep away from limestone as it releases carbons and turns into quick-lime when cooked.

You don't need a tray to carry the stones. You can use damp (not soaking wet) news paper, or damp (not soaking) 100% cotton or wool cloth. Man made fibers are plastic and melt at low temperatures.

One method of using stones to heat a space is to hang them in 100% natural fiber net bags.

The correct way to heat stones or other materials is to build a fire and let it burn down to hot coals. It takes about 30 minutes to reduce a quantity of wood logs to red hot coals. Then heat the stone with the coals.

I would suggest moving some coals to the side, placing your rocks, move more coals around and over and keep a fresh fire of fuel burning the fuel to hot coals.

You only need to heat one hand sized rocks about 20 minutes, or 30 minutes... They won't get hotter beyond that.

Care should be taken with stone and brick, as they can explode when heated due to trapped moisture inside. So place them and don't muck around that part of your fire until they are hot. Once you have heated a stone or brick or chunk of concrete and it hasn't cracked or failed, its a reasonable bet you can reheat it again and again.

I've used 5 pound coffee cans of river sand (which is abundant around these parts) heating the whole container in hot coals, the transferring the coffee can to a metal bucket. to carry it into my shelter/tent.

If you are planning on doing this over night, I strongly suggest you build a ground oven, basically a hole in the ground that you move red hot coals to - you can heat a lot of rocks in there at one time.

It takes a bit longer because you ideally want to have hot coals in your minor pit for about an hour to heat the surrounding soil. once that is hot the majority of your heat will be trapped in the oven, thus heating the rocks more.

Its called an 'oven' because earlier people would heat the rocks, scoop out the remaining hot coals, put in their flat rock upon which they would bake bread. The dough is placed on the baking stones (flat rocks that were not heated in the fire sitting on a bed or heated river stone) then a cover of branches and leaves is put over the whole whole to insulate the top. 35-40 minutes the top is removed and the break is all golden brown and baked.

You're using the heat of your rocks to bake - how cool is that?


Another trick with heated stone is to boil water.

River stones (well rounded stones) can be heated then dropped in water and the water will eventually heat up to boiling.




Yes the water gets ashy and sooty... one way to reduce that is to wrap your stones in wet leaves which will burn off in those 20 minutes but you get less wood ash. Wood ash combined with water makes amongst other chemicals lye - you seriously don't want to ingest lye water.

However a simple sheet of cloth like an old pillow case is enough to filter out the majority of the soot and ash if you want to use the water for bathing. Since you do have it boiling you will want to add fresh cold water which will lower the acid level from the lye to much safer levels.

Understand lye was used in the saponification of fats to make soap. So a little lye on your skin will clean you and not kill you. High concentrations of lye will eat through anything, including your skin.

Lime will do the same thing, thus you need to be very careful with limestone, which when cooked is reduced to lime. even heating lime stone will cause some of it to become quick lime which will dissolve into your water.

When camping I do a 'double boiler' method. The water that the rocks go into is 'sacrificed' so it doesn't matter how dirty it gets. Once you get that water to boiling, you remove the rocks you used to heat it, add fresh rocks, then use a pan, pot or even a plastic bag with fresh water set into the boiling water. You get clean boiling hot water. Yes you can cook with it, make tea - whatever.

Boiling bags that are resealable work well with boiling stone water.

Insulation. So not metal... you want to wrap it in something that traps air, say wrap a blanket around your stones a few time... this will slow the amount of heat radiating out of your stone.

Straw mulch also works well with trapping heat.

I use 1 gallon plastic milk jugs filled with water set on their sides along plants in my garden. I use mulch around three sides of the jug and around the plant to help direct the heat loss toward the plant. I leave the top 2 inches of the side facing up exposed to sunshine... Sunsets and the water radiated sufficient heat to stave off light frost for shorter plants.

Larger plants I tent with old sheets covering in the evening just as the sun is setting and removing in the morning.

So even a thin sheet can trap and hold heat.

Ban Rocks !!!

Beans in a sack?

VERY interesting, Japanese friend.

I will take beans in bangs with me and make sure to also use rocks to keep me warm during the freezing weather right now.
Thanks to both of you for your suggestions.

Will look into this. Thanks.

THIS ^^^^ IS ^^^^^ TRUE