I'm excited to learn how part 3 goes. This might be a project our church could do together. I can see us hanging out after services, baking pizza, sitting on a cob bench, enjoying the garden and having fun. I think the process of building it could be a good bonding experience, and a way to share trust.
We need to do this everywhere now, as we don't know how long any food supply will last, or energy. We are slipping back into medieval times, which I find rather interesting. Got the land, the horses, and the forests.
the first layer is your heat sink, so you want pure thermal mass, heat absorbing materials. Straw is an insulator, not a heat sink. The second layer, you want to insulate the heat absorbed in the first layer, so the second layer is high straw (insulator) content. If you let the oven dry slowly, the inside layer does not crack with heat, so no worries there.
The insulation is as much straw as possible, coated with as little clay as possible. I usually use clay soil, so that is often at least 50% clay/50% sand. When it dries, the clay acts like hairspray and holds the straw in place.
Yes, Chloe King, you have the proportions correct...BUT...that is the mix for the particular clay that we were using. What you want to do is start with about 25% clay, 75% sand, and feel the mixture. If it sticks a ton to your hands, making it difficult to work, then up your sand content. If you find that as you are forming, the mix is difficult to keep stuck together, then up the clay content. The reason is that there are many many many different kinds of clay...so you want to create a ratio that is optimal for your particular ingredients. Hope that makes sense....
Any exposed straw would ignite and then just leave a void. Not really a big deal, but you really want the pure thermal mass for higher performance of the oven. And the inner layer doesn't crack if you let it dry really slowly. If you light a fire while it's all still wet, then yes, it would crack like crazy. If you do get cracks, you can always fill them in with the same clay mix that you built the oven with.
You absolutely can take a break and build the oven slowly over time. I recommend covering it with plastic to slow down the drying process. Covering also helps keep the oven drying slowly if it is very how. The slower it dries, the less risk of cracking. As you build the 1st layer, poke some shallow dimples with your thumbs into the outside surface of the thermal mass layer. This gives the insulating layer a physical key.
ScorpTac Thanks for the reply. :) If you remember to, let me know when you find out the date. These things only seem to happen when I'm not looking, and I'm determined to catch one.
Yes I would love to! Unfortunately my summer work schedule doesn't allow for any time taken off, but depending on when an where I'm still dead-set on doing this.
Sorry to keep you waiting! Someone else is editing the videos for me, and I upload them as soon as they are complete. Hopefully part 3 will be ready soon, and then we'll be adding other natural building tips. Thanks! Sigi
Hello, I have been following your instructions, which I find excellent. What I want to know is, does it matter if there is a few days break between the thermal mass layer and the insulation layer, or is it necessary that it is done all in one go. My hubby and I are building the oven and I must say it is a lot of work, even though it is enjoyable. Also the weather has been very very warm. 40 celsius today in Greece. Any effects from that?
The bracing is not normally needed. We took all of the sand out the same day we built the oven. The clay inside was not dry enough & looked like it was going to collapse a bit without the sand in place, so we braced it for a few days until it was dry enough to hold. You can prevent the issue by pulling out only 1/3 to 1/2 of the sand the first day. This speeds up the drying process inside but still provides support for the clay dome. Clean the remaining sand out a little bit more each day.
I think I get it, but just tomake sure: 50% clay-soil, 50% sand, and the clay-soil is 50% clay, 50% soil (or like you said,sand), leaving you with only 25% pure clay. I'm just wondering because I have a box of pure clay and bags of pure sand. Also, because I dont need so big an oven, how small can I go? Thank You soooo much for this helpful video. :)) The best one out there!
Please can you put the subtitle option to their videos? We are a group of friends from the ovens and not knowing their language rather difficult to understand us. Greetings from Spain.
i noticed in one of the shots it looks like there is bracing inside the oven once the sand is removed. Is that required to hold up the clay until it dries? Or just precaution? How long should it stay in place? Thans - great videos!
Would suggest about the same mix to lay clay bricks together to build a chimney. and do you think it would be weather resistant, instead of using cement?
+Gilberto Nino Definitely do not use cement at all for any of this. You can use the same mixture to make adobe bricks, yes. And then lay them together with a mortar made from the same material as well. Clay cannot freeze if it is wet, or it will craze and lose structural integrity. It will also erode in lots of rain. So if you have either condition, then you need a roof or several coats of lime plaster
So there is no way for axample to build a room of bricks with clay and be weather resisten right ? Thank your your time, hope you had beutiful Merry chrismas!
You don't add straw to the cob. I have been reading round how to's and felt that straw would add strength - see "balinsky-dot-com-slash-gallery-slash-coboven". Can you explain the pros and cons of straw/no straw? Excellent video, thanks.
hi! I would happily change any settings to allow subtitles to be viewed. But I don't see that as an option unless I upload a caption file. I do not know Spanish so cannot translate the video. If you know of a setting that would do this automatically, please let me know and I will gladly change the setting for you.
I bought a commercially made pizza oven, it's uninsulated but works well, however, it only keeps its heat for about 4 hours, I've been exploring insulation methods and it seems cob may be my answer since it will also add thermal mass. Is this a viable option?i.e. To add a cob layer on top of a pre-existing stone dome oven?
I would just add insulation to the outside, not more mass (unless you have less than 4" thick mass). Otherwise it will also take longer to heat up. Cob is not insulation, just mass. So you want a mix that is straw and just clay slip (like a clay milk shake)...and pack that around your existing mass. Once dry, you can plaster over the straw.
Yeah it's a pretty thin material, i'd say 3-4" at a guess. I think I'm trying to kill multiple birds with 1 stone, I want to protect the existing structure from the elements (we get very harsh winters here in Sweden) and I want to increase the residual cooking time, which is why I thought adding mass would be the way to go. So where i said insulation, I guess i meant "protection", but at the same time, I want to make the oven retain it's heat for longer too.
depending on the size of your oven, the typical ideal amount of mass is 4" and typically 1.5x that for insulation. Mass is the heat battery. Insulation keeps the battery from releasing heat to the exterior. In terms of protection from harsh winters, the only guaranteed solution is to build a roof over your oven.
Aaah - 4.26 -there's the straw! Sorry. So no straw in the first layer. Doesn't this crack with the heat? Would straw in this first layer ignite and blow the thing apart?
you can build your base any way you like. It just needs to support the substantial weight of the oven and be built to the height that you want your oven to be for cooking. The base is just supporting, it is not part of the thermal system of the oven itself (ie, the base does not heat up when you fire up the oven)
+Michele Greetings There is clay soil in most places throughout the U.S. So I generally dig it out of the ground. If you really do not have clay in your soil, then you can purchase clay from a pottery supplier. (Generally cheaper to purchase dry clay)
sorry my english. why did you use for the first layer only 25% clay, but not 100% clay. the tandoors makers use 100% clay and ceramiks gifts like cup, bowl include only clay. thank you.
biz bu sekilde cocukken hamam kizdi oyunu yapardik yalniz icinde ates yakmazdik su doldururduk kimden taraf cabuk cokerse yani yikilrsa o yenilmis sayilirdi Turkiyede yapardik simdi hollandada bu malzemeleri almak icin en azinda 1000 euro harcamk lazim
Hi, please make such type of oven with gas fire 🔥 system besides wood fire ... Because wood is expensive in our country than gas 😌😔 i hope u will respond then i will subscribe 😄
I'm excited to learn how part 3 goes. This might be a project our church could do together. I can see us hanging out after services, baking pizza, sitting on a cob bench, enjoying the garden and having fun. I think the process of building it could be a good bonding experience, and a way to share trust.
We need to do this everywhere now, as we don't know how long any food supply will last, or energy. We are slipping back into medieval times, which I find rather interesting. Got the land, the horses, and the forests.
the first layer is your heat sink, so you want pure thermal mass, heat absorbing materials. Straw is an insulator, not a heat sink. The second layer, you want to insulate the heat absorbed in the first layer, so the second layer is high straw (insulator) content. If you let the oven dry slowly, the inside layer does not crack with heat, so no worries there.
Thank you, will be trying the same method.
The best TH-cam video on cob ovens so far.
Greetings from Latvia.
I want to build one this year on my back patio for pizzas and turkeys. Hopefully part 3 will be here soon.
The insulation is as much straw as possible, coated with as little clay as possible. I usually use clay soil, so that is often at least 50% clay/50% sand. When it dries, the clay acts like hairspray and holds the straw in place.
Yes, Chloe King, you have the proportions correct...BUT...that is the mix for the particular clay that we were using. What you want to do is start with about 25% clay, 75% sand, and feel the mixture. If it sticks a ton to your hands, making it difficult to work, then up your sand content. If you find that as you are forming, the mix is difficult to keep stuck together, then up the clay content. The reason is that there are many many many different kinds of clay...so you want to create a ratio that is optimal for your particular ingredients. Hope that makes sense....
Any exposed straw would ignite and then just leave a void. Not really a big deal, but you really want the pure thermal mass for higher performance of the oven. And the inner layer doesn't crack if you let it dry really slowly. If you light a fire while it's all still wet, then yes, it would crack like crazy. If you do get cracks, you can always fill them in with the same clay mix that you built the oven with.
You absolutely can take a break and build the oven slowly over time. I recommend covering it with plastic to slow down the drying process. Covering also helps keep the oven drying slowly if it is very how. The slower it dries, the less risk of cracking.
As you build the 1st layer, poke some shallow dimples with your thumbs into the outside surface of the thermal mass layer. This gives the insulating layer a physical key.
Ah... Wagon Wheel in the background... That's feel good music right there. Can't wait for my oven building party.
Where will your party be held? I'm looking for one of these events to invite myself to. >_< Haha (I laugh but I'm totally serious).
Kozelka it'll be in southeast idaho. But I have no idea when.
ScorpTac Thanks for the reply. :) If you remember to, let me know when you find out the date. These things only seem to happen when I'm not looking, and I'm determined to catch one.
Kozelka Still want to attend a Cob oven building?
Yes I would love to! Unfortunately my summer work schedule doesn't allow for any time taken off, but depending on when an where I'm still dead-set on doing this.
Nice job.. Now i Stay Tuned 4 part # 3 :)
Thnx for the vid Dahlin 👍👍👍👍👍👍
happy christmas
Sorry to keep you waiting! Someone else is editing the videos for me, and I upload them as soon as they are complete. Hopefully part 3 will be ready soon, and then we'll be adding other natural building tips. Thanks! Sigi
Hello, I have been following your instructions, which I find excellent. What I want to know is, does it matter if there is a few days break between the thermal mass layer and the insulation layer, or is it necessary that it is done all in one go. My hubby and I are building the oven and I must say it is a lot of work, even though it is enjoyable. Also the weather has been very very warm. 40 celsius today in Greece. Any effects from that?
The bracing is not normally needed. We took all of the sand out the same day we built the oven. The clay inside was not dry enough & looked like it was going to collapse a bit without the sand in place, so we braced it for a few days until it was dry enough to hold. You can prevent the issue by pulling out only 1/3 to 1/2 of the sand the first day. This speeds up the drying process inside but still provides support for the clay dome. Clean the remaining sand out a little bit more each day.
Great video. Does your stone base go all of the way down to the frost line? Or is that not important?
@scsteeldrums yes! Absolutely! It's not as fun as doing it with a group, but absolutely doable as a one person project. Good luck!
I think I get it, but just tomake sure: 50% clay-soil, 50% sand, and the clay-soil is 50% clay, 50% soil (or like you said,sand), leaving you with only 25% pure clay. I'm just wondering because I have a box of pure clay and bags of pure sand. Also, because I dont need so big an oven, how small can I go? Thank You soooo much for this helpful video. :)) The best one out there!
thx for your sharing
If you are working with a box of pure clay and a bag of sand, what you recommend as the easiest way to blend them?
most definitely! great idea!
Please can you put the subtitle option to their videos?
We are a group of friends from the ovens and not knowing their language rather difficult to understand us.
Greetings from Spain.
i noticed in one of the shots it looks like there is bracing inside the oven once the sand is removed. Is that required to hold up the clay until it dries? Or just precaution? How long should it stay in place?
Thans - great videos!
I have read that the height of the dome can be from 50% to 75%. From your experience does the 75% cook any better than the 50 % height? Thanks
Do you for insulation layer mix only straw with clay or straw with clay + sand?
Thanks
Hi Sigi, can we use licht clay staw as the second layer and plaster there one the finiching layer
Sigi,question/note if i think good - into insulation layer mix you dont add cob mix but original clayey soil to bind the straw,right? Or?:)
I read that the height of the dome can be from 50% to 75%. From your experience does the 75% cook any better than the 50 % height Thanks
sorry for my lack of patience, but the suspense is killing me....when is part III going to be ready?? :)
How many bedrooms does this thing have? 😃👍❤️
Are you still making these?
OK Muchas Gracias.
Sigikoko is Part 3 coming?
What happens if you build the whole thing out of clay and straw without any sand
Would suggest about the same mix to lay clay bricks together to build a chimney. and do you think it would be weather resistant, instead of using cement?
+Gilberto Nino
Definitely do not use cement at all for any of this. You can use the same mixture to make adobe bricks, yes. And then lay them together with a mortar made from the same material as well. Clay cannot freeze if it is wet, or it will craze and lose structural integrity. It will also erode in lots of rain. So if you have either condition, then you need a roof or several coats of lime plaster
So there is no way for axample to build a room of bricks with clay and be weather resisten right
? Thank your your time, hope you had beutiful Merry chrismas!
Can this be done by one person?
You don't add straw to the cob. I have been reading round how to's and felt that straw would add strength - see "balinsky-dot-com-slash-gallery-slash-coboven". Can you explain the pros and cons of straw/no straw?
Excellent video, thanks.
hi! I would happily change any settings to allow subtitles to be viewed. But I don't see that as an option unless I upload a caption file. I do not know Spanish so cannot translate the video. If you know of a setting that would do this automatically, please let me know and I will gladly change the setting for you.
Why have the oven that high?js it looks high.
please let me know what you think or if you have any questions!
Can I use sand at the beach
I bought a commercially made pizza oven, it's uninsulated but works well, however, it only keeps its heat for about 4 hours, I've been exploring insulation methods and it seems cob may be my answer since it will also add thermal mass. Is this a viable option?i.e. To add a cob layer on top of a pre-existing stone dome oven?
I would just add insulation to the outside, not more mass (unless you have less than 4" thick mass). Otherwise it will also take longer to heat up. Cob is not insulation, just mass. So you want a mix that is straw and just clay slip (like a clay milk shake)...and pack that around your existing mass. Once dry, you can plaster over the straw.
Yeah it's a pretty thin material, i'd say 3-4" at a guess. I think I'm trying to kill multiple birds with 1 stone, I want to protect the existing structure from the elements (we get very harsh winters here in Sweden) and I want to increase the residual cooking time, which is why I thought adding mass would be the way to go. So where i said insulation, I guess i meant "protection", but at the same time, I want to make the oven retain it's heat for longer too.
depending on the size of your oven, the typical ideal amount of mass is 4" and typically 1.5x that for insulation. Mass is the heat battery. Insulation keeps the battery from releasing heat to the exterior. In terms of protection from harsh winters, the only guaranteed solution is to build a roof over your oven.
Thank you for your advice, I'm very grateful.
Aaah - 4.26 -there's the straw! Sorry. So no straw in the first layer. Doesn't this crack with the heat? Would straw in this first layer ignite and blow the thing apart?
please i need to know what to do for the base how to make in order to keep the heat in thanks
you can build your base any way you like. It just needs to support the substantial weight of the oven and be built to the height that you want your oven to be for cooking. The base is just supporting, it is not part of the thermal system of the oven itself (ie, the base does not heat up when you fire up the oven)
where do you get the clay? ,,I have no idea where to get some here where I live in Iowa
+Michele Greetings
There is clay soil in most places throughout the U.S. So I generally dig it out of the ground. If you really do not have clay in your soil, then you can purchase clay from a pottery supplier. (Generally cheaper to purchase dry clay)
not an answer,,,,duh
She answered your question. You can dig clay out of the ground in your backyard or buy it from a pottery supplier.
okay.....still waiting for part three.
We used to make every year new in our village.
parabéns. .! gostei
yes, exactly!
Hi. How much clay and sand did you use?
+Gilberto Nino exact amounts depend on your clay (different clay has different stickiness). But a good starting point is 25% to 30% clay.
thanks awesome,.:)
What did you get a degree in, you are so knowledgable.
+Nicole Culajay First fine arts (sculpture) with a math minor, then graduate school for architecture. And I build stuff a lot :)
Part 3 ?????
sorry my english. why did you use for the first layer only 25% clay, but not 100% clay. the tandoors makers use 100% clay and ceramiks gifts like cup, bowl include only clay. thank you.
to minimize cracking as it dries. If you use 100% clay, you would need to control the drying so it was very slow over several monthss
thank you!
Why not use perlite instead of straw
use whatever insulation is local to where you live (where I work, the least expensive, most sustainable option is straw)
biz bu sekilde cocukken hamam kizdi oyunu yapardik yalniz icinde ates yakmazdik su doldururduk kimden taraf cabuk cokerse yani yikilrsa o yenilmis sayilirdi Turkiyede yapardik simdi hollandada bu malzemeleri almak icin en azinda 1000 euro harcamk lazim
Hi, please make such type of oven with gas fire 🔥 system besides wood fire ... Because wood is expensive in our country than gas 😌😔 i hope u will respond then i will subscribe 😄
wow.. 3:19 heheheee
Did You make it with woodprix instructions?
u can directly build ur cob oven even w/o sand dome its more easier than this method