Alternative Heating Methods: Coffee Can Heater

One of the most requested topics from our “What’s Coming Up Next” post was to discuss some alternative methods of cooling and heating your home. We have recommended in the “Car Kit” portion of our Emergency Preparedness Plan that you place a Coffee Can Heater in your car. These heaters could also be useful in a home if you had no other options available and needed to thaw yourself out a little bit.

A while back, we gave a little tutorial for how to make a coffee can heater, but we had a reader (David H. from Washington) who has refined and perfected this method and makes it so that the outside of the can doesn’t get too hot to the touch. This is a tutorial and pictures put together by him and posted here with his permission. This is the best part about our blog, we learn from our readers every day. You guys are the best!

How to Make a Coffee Can Heater

Items Needed:
1 – Empty tuna can (not shown)
2 – 1 lb cans: 1 empty, 1 unopened
1 – # 10 can empty with plastic lid
1 – Roll toilet paper
1 – Can spray foam insulation
1 – Book or small box of matches
1 – Bottle isopropyl alcohol

Optional Items:
1 – Empty popcorn tin (Three flavor type)
2 – Additional rolls toilet paper

Instructions

Step 1: Clean and dry the empty cans and remove labels if desired.
Step 2: Remove cardboard tube from a roll of toilet paper.
Step 3: Place toilet paper into 1 lb can by squeezing bottom of roll to get it started then pushing it in with a twisting motion.
Step 4: Place the tuna can into the bottom of the # 10 can.
Step 5: Spray a small amount of foam insulation around the tuna can.
Step 6: Place the 1 lb can with the toilet paper into the # 10 can on the tuna can.
Step 7: Spray insulation between the sides of the two cans. Fill the foam about halfway up the side of the 1 lb can.
Step 8: Place an unopened 1 lb can on top of the can with the toilet paper roll. This directs the insulation upward as it expands and prevents it from expanding over the top of the toilet paper can. Let it sit for an hour or more so you can determine the amount of expansion.
Step 9: Spray in a second layer of insulation, allowing for enough expansion to bring it to the top of the # 10 can. Set this aside for eight hours to allow the insulation to fully expand and set up.
Step 10: Remove the unopened can and use a long-bladed utility knife or a sharp kitchen knife to trim the excess insulation. Slice the insulation from the rim of the # 10 can to the rim of the 1 lb can. If the insulation is still wet inside, it will get on the blade of the knife and is difficult to wipe off. Scraping with a straight edged (not serrated) is the best way to get it off.
Step 11: Pour some alcohol onto the toilet paper and light it with a match. The insulation may burn briefly and char, especially if it hasn’t set up completely. Do this outdoors or with adequate ventilation to avoid smoke buildup in the house.

After using the heater for 30 minutes, the # 10 can was cool enough to hold at the top. The rim gets hot enough to melt the plastic lid if placed on it right after using the heater.

Step 12 (optional): If you choose to use the popcorn tin option, the heater, two extra rolls of toilet paper, and a bottle of alcohol will all fit in the popcorn tin with room for a flashlight, some tools, or other similar items. The popcorn can lid is an easy way to put out the fire in the coffee can heater and it won’t melt. Just set it on top and the flames go out.

Some observations from David. Originally, I hoped to make a self-contained heater with room for a small bottle of alcohol and some matches. This can be done by not using the tuna can, however, the 1 lb can with the toilet paper sits too low in the # 10 can and the flames may die from poor air circulation. Drilling a series of holes a couple of inches below the rim of the # 10 can through the insulation will help with the air flow. Use a hammer and nail to make starter holes so the drill won’t skate. Metal burrs may be found around the holes and the metal is sharp, so a file should be used to remove the burrs.

With four attempts at making the heater, I used about 1.5 cans of spray insulation. I estimate that one can could produce 3-4 heaters.

Note from Jodi and Julie: We hope this has been helpful for you. If you make one of these heaters using this method feel free to share about it in the comments or post a picture in our facebook fanpage. Thanks again to David for submitting this!

  • Alford67

    another alternative to heating/cooking without power is the Swedish Fire Torch…. there is a video on Youtube showing how to make one using a split log…. 

  • http://twitter.com/toadface07 rebecca berman

    I’m wondering how long this will burn once lit – we just had a snow storm here in western WA and the power has been out in some places since last Wednesday (5 days ago) and our power went out for a bit and we found out that even tho we have gas stove and heat it doesn’t work with the electricity out (ha we were told by both the landlords and the gas company that it would still work without electricity — ha they are wrong. We have an alternate cooking plan now but no alternates with heat. But trust me we will shortly.

    • swaz

      I also have a gas stove with an electric start ,all you need to do is turn on gas and start with a match or grill lighter as you would if you had a pilot that had gone out.

  • Centuryhouse

    Also – 1) make sure the 1lb can you use is actually just metal, not metal with a coating inside which many cans have, and 2) I haven’t tried this but was thinking that maybe a non-coated, metal clothes hanger could be folded over the top of the can and be used to set a small can / kettle on.

  • Centuryhouse

    Just curious – how long will one roll of paper burn? Can the fire be blown out? I’m asking, because if you have the plastic lid or have drilled the holes for airflow, you can’t smother it out.

    Thanks!

  • Mredxoxo

    You should place a warning on this about not using it in a closed space.  fire burns oxygen.  This was listed as a car kit item in another page.  it should not be used in a car. 

    • http://foodstoragemadeeasy.net Jodi – Food Storage Made Easy

      From what we have read it will be ok as long as you vent your windows. We have seen this recommended for use in a car quite often.

    • http://foodstoragemadeeasy.net Jodi – Food Storage Made Easy

      From what we have read it will be ok as long as you vent your windows. We have seen this recommended for use in a car quite often.

    • Kathy

      Alcohol is used because it does not produce carbon monoxide as it burns. We were taught how to make these while in college during out public health orientation to country home visits. The larger the roll of TP the longer it burns. It is a slow burn with very little flame if down right. It was made especially to use in a car foot well if stuck in snow.

      • Kathy

        Forgot to mention, we just used ordinary large metal coffee cans, toilet paper that was at least 2-3 ply, stuffed in the can, with cardboard tube removed, ordinary rubbing alcohol, a box of stick matches. Cut holes around the rim of the can with a bottle opener, (makes triangles – about 4 or 5 depending on the size of the triangles) The ‘fire’ is a soft blue flame. Can did not get hot. Did not burn carpet in foot well where placed. I also carried bottled water. Can be used to put out flame if no longer needed. Put new roll of TP in can for next time.

  • R_T_Cowgirl

    How much alcohol do you pour over the TP at one time?

  • Maddy

    Electricity went out for 24+ hours at my home, and there was too much snow, wind, and ice to go fetch the logs in my detached shed.. I had some logs, started the fire and kept warm. The heater really helped when only embers were left. I put it on the fireplace hearth for safety, and used it to make some hot water (used a TIN cup) for tea. I used some foam to space the smaller can in the center, cut out a donut-shaped ring from the removed lid, pressed it down and then had some sand (stored in a baggie) to pour into the top. This way the insulation didn’t burn! To use it to heat up water, without extinguising it, I used a metal tribet (the type you put on an electric coil range to protect ceramic vessels) and put the tin cup on top. I had the snacks and stuff to eat, but having hot tea…nice.

  • Elwin

    Just out of curiousity, would there be any outgassing/toxic fumes from the insulation during operation of the heater? I’m kinda wondering if something like perlite or vermiculite wouldn’t be a safer choice. Both are recommended if one is making a rocket stove.

  • Brchbell

    BTW: The round containers of raisin’s at the store the lid from those fit the 30 ounce fruit/veggie can’s. a little loose on the down sized 29 oz cans. Forget the thing above and just use a can about the same size as the toilet paper and remove the tube and squeeze the TP into the can and you have your heater ready to go. Pour on the rubbing alcohol and light it and you have heat above the can not in the can! Try it and see! Toilet paper does not burn, the heaters last forever!

  • Brchbell

    BTW: The round containers of raisin’s at the store the lid from those fit the 30 ounce fruit/veggie can’s. a little loose on the down sized 29 oz cans. Forget the thing above and just use a can about the same size as the toilet paper and remove the tube and squeeze the TP into the can and you have your heater ready to go. Pour on the rubbing alcohol and light it and you have heat above the can not in the can! Try it and see! Toilet paper does not burn, the heaters last forever!

    • beingjennifer

      Can you explain more precisely?

    • beingjennifer

      Oh, I just read your previous post. I think I got it. TY.

  • prepared

    Directly from Dow’s Great Stuff insulating foam website: “Cured foams and adhesives are combustible and should not be applied to areas exposed to high temperatures, such as around lighting fixtures and radiators. When the cured foam is burned, toxic gases are released.”

  • Cherlynn

    I’m wondering what heat on the can? Mine are in baby formula cans that are foil lined cardboard with a metal ring at the top. Had 20 of them and they ran nonstop for 3 weeks Dec. ’08 no fumes, the carbon detector never raised at all the cans were never hot. Above the flame is hot but we can even run our hands over a lite one across the TP and it’s not hot. Seems like ya all are adding a lot of extra work to a simple project! I found the 29 to 30 OZ fruit/veggie cans work great. Make sure you are using plain ordinary rubbing alcohol and not something else! Tried one of the fruit cans and it’s been burning over an hour and not hot at all. Due to our ice storms,ect we use these al ot each and every winter. They don’t get hot if you make them right and use plain unscented 70 to 91% isopropyl alcohol.

    • http://foodstoragemadeeasy.net Jodi – Food Storage Made Easy

      Cherlynn, I’m not sure what I did wrong but in my original tutorial I accidentally used a hot chocolate canister that was foil-lined cardboard and it caught fire and burnt me in the process. It also was very hot to touch all around the container. It incited a lot of debate in the comments about what would work better and that is where this tutorial came from. A reader submitted it to us as a solution. It seemed like a good option to me, I don’t think the foam material ever burns so I wouldn’t think the “toxic gas” from it burning would be an issue. Like you said only the alcohol burns. The foam is just as an insulator to protect you from the heat.

  • http://www.facebook.com/profile.php?id=1059284734 Tamra Aichele

    What are the dimensions of the 1# can? I tried a 1#4oz can that was the same size of all the other 1# cans in the cupboard and there was NO way I was going to get a whole roll of Kirkland TP in there (and yet he used KS paper too) even with the cardboard out. I had to find a half used roll and it was still very, very tight. Which, if I stored two extra rolls in the “kit” to resupply as suggested, there’s no way I would get them in there for a refill once all the insulation is in. Suggestions anyone?

  • http://www.facebook.com/profile.php?id=1059284734 Tamra Aichele

    What are the dimensions of the 1# can? I tried a 1#4oz can that was the same size of all the other 1# cans in the cupboard and there was NO way I was going to get a whole roll of Kirkland TP in there (and yet he used KS paper too) even with the cardboard out. I had to find a half used roll and it was still very, very tight. Which, if I stored two extra rolls in the “kit” to resupply as suggested, there’s no way I would get them in there for a refill once all the insulation is in. Suggestions anyone?

  • Ctwniki

    Is there no risk of any chemical type fumes from the insulation heating up? Any ideas if this could be used to heat a cup of water or cook an egg?

  • Ctwniki

    Is there no risk of any chemical type fumes from the insulation heating up? Any ideas if this could be used to heat a cup of water or cook an egg?

    • Marilyn

      Used something like this called “Kitchen in a Can” using a single roll of toilet paper cardboard tube taken out and stuffed into the 1 qt paint can with lid for storage purposes. When ready to use remove the lid, add the alcohol, place 3 3/4″ plywood clips fit over the rim of the can. Put the clips onto the rim of the can spaced equally, set the paper/alcohol on fire and put your pan of food or water on top of the clips and it will boil water in no time. I used i his after a hurricane came through our area and we were without electricity for a number of days. In time of need I helped a neighbor when she was trying to boil water using their grill. Both were impressed with my unit and determined to make one. Fortunately I had the materials so on hand and promptly made one for them too.

  • http://blog.covermatecovers.com/2010/09/second-time-around-blog-reviews-covermate-food-covers/ Pan Covers

    Interesting way to make use of recycled food storage containers. Creating a homemade heater may keep one warm when in a pinch. Thanks for sharing this info.

  • http://blog.covermatecovers.com/2010/09/second-time-around-blog-reviews-covermate-food-covers/ Pan Covers

    Interesting way to make use of recycled food storage containers. Creating a homemade heater may keep one warm when in a pinch. Thanks for sharing this info.

  • Bonnie

    An empty quart paint can makes a fantastic container for the toilet paper and it comes with a lid. My local paint dealer was happy to give me one for no cost.

  • Bonnie

    An empty quart paint can makes a fantastic container for the toilet paper and it comes with a lid. My local paint dealer was happy to give me one for no cost.

  • Dogwoodcottage

    Hi the alternative is ashes from your wood stove makes the best insulation and its FREE!

  • Npp1966

    Good question on if the insulation releases toxins. Maybe a solution for that would be to spray the insulation within 2 – 3 inches of the top of inside can and then finish off with maybe plaster of paris (does it melt??). Orfill can to within an 1/2″ to 1″ of top of inside can and put a thin top coat of thin set or concrete . These last two may increase the weight too much though.

  • Npp1966

    Good question on if the insulation releases toxins. Maybe a solution for that would be to spray the insulation within 2 – 3 inches of the top of inside can and then finish off with maybe plaster of paris (does it melt??). Orfill can to within an 1/2″ to 1″ of top of inside can and put a thin top coat of thin set or concrete . These last two may increase the weight too much though.

    • Dogwoodcottage

      Hi the alternative is ashes from your wood stove makes the best insulation and its FREE!

      • wendy

        my husband suggested sand could also do the job which is also free!

  • shari

    Will the spray insulation release any toxins when it gets hot?

  • shari

    Will the spray insulation release any toxins when it gets hot?

  • Kimmyjling

    Do you think this will work with cotton flannel instead of toilet paper?

  • Kimmyjling

    Do you think this will work with cotton flannel instead of toilet paper?