This video shows how to test soil to determine if there is enough clay content to use the soil for construction - cob, adobe, clay plasters, and more.
ความคิดเห็น • 93
10 ปีที่แล้ว +7
Thank you for taking the time to educate us on this very important aspect of cob that I've rarely seen touched on in other videos. We are using yours and many other ideas on building our cob ovens.
I am starting plans on building my home in Ayangue, Ecuador. I know the foundation has clay and would love to have a Cob Oven. Its a wonderful view of the ocean, so a lot of outdoor living will take place.....appreciate the demo!
the exact percentage of sand to clay depends on the type of clay. So I recommend making some test bricks with a variety of ratios and seeing which of the bricks is strongest. Likely your ideal percentage will be somewhere between 15% to 25% total clay content, but I've had clay be as low as 7% and as high as 30%. Make your bricks about the proportions of regular fired bricks (not too skinny in any dimension), then let them dry out, and then break them to see which is strongest.
"total clay content" as in the amount of clay minerals or like the amount of mud/ground material to other ingredients? also is this for the end mixture with straw and whatever in it or just for the mineral content?
The height measurement technique does not account for the fact that the jar is rounded near the bottom. It's best to take a equivalent jar and make your own graduation marks, then translate those marks to the sample jar. Or just mark the sample jar to start with.
Good vid, thanks. A thought about using a cylindrical jar: a more accurate measure might be to empty the jar, fill it to the first line with water and measure that volume. Do the same with the second line and compare the two volumes. The container's shape becomes irrelevant.
Thanks, I'll give it a go as soon as the weather fines up. I'm really looking forward to seeing how this turns out. I've got a few projects I would like to complete using cob, this is going to be interesting... Thanks again for your help.
the actual amount of clay that is ideal depends on several variables. 1st is the actual type of clay. Different clay absorbs different amount of water, thus swells different amounts, thus gets stickier or less sticky. That said, the highest percentage of clay I have ever used is 30% (lowest is 8%, to give you a sense of the variation). My gut instinct is that 2 parts clay is way too much and it will shrink and crack a lot (especially if you are building a thermal mass layer without straw).
I guess that many people (like me) think that just after the jar test, natural builders have a way to separate clay and sand in two batches. I still have some doubts about the process of making cob... in most tutorials they already have the sand and clay separated in batches, and then show you how to mix them with straw. But if I want to extract them from my own soil I should do this jar test. Let's say my soil is 60% sand, 20% silt and 20% clay. What I should do after I discover it by the jar test? That's what I still don't understand and for sure many people as well.
This test allows you to know the proportions in your particular soil. That becomes your baseline, so you know if you need to augment your soil with additional clay or with additional sand in order to get a good, strong, non-cracking mixture for clay materials (cob, adobe, clay plasters, etc.) You don't need to separate the clay from the sand in all of the soil, you are just adding sand or clay to adjust your existing proportions.
+buildnaturally Is there an allowable measure of silt that would work in cob? I've read that silt in cob is a no no and having to dig it all myself, I'm concerned I might need to over complicate the process to remove the silts. Any tips or advice?
you should fill it with other material, either store bought or found somewhere else, until it's the ideal mixture for you. i suppose you also could wait for the sand to settle (around 10-30 seconds) and then separate the two, same goes for silt although i don't know how difficult that is, since i haven't searched for an answer yet also read the top comment made by the channel if you need more info. there's a lot more detail there. it's apparently not too complicated if you just try it out and see what works best
I been wanting to build a pond on my property and its over 60% sand. Today I dug another 6ft hole about 50 ft away from creek and appears to look better just waiting for the jar contents to start settling. I believe I may end up moving the pond away from the creek to get the better clay content and then adding another 3 or 4 inchs of clay on top. 20yards of clay is $150 delivered 15 miles from site and I wanted 130 yards to get a good seal.
@anothergoogleuser As an example...take our shake test as approx 1 part sand to 1 part clay (for ease of math), that is a 50% clay content. You want 25%, so you need to add 1 part sand for each 1 part soil, which will give you a final mix of 3 parts sand (2 from the pure sand and 1 from the soil) to 1 part clay (1/2 the makeup of the soil) or 75% sand and 25% clay. Then I recommend making test bricks to find out the exact percentage of your clay that will be strongest.
Thanks, I needed to figure out how to detect clay in sand/dirt because I am making a clay battery, and I heard that clay holds more microbes then dirt does.
You show two lines. How do you know where to draw the bottom line, if the contents are still settling? I don't know how to distinguish the "sand" layer top from the beginning of the clay content section. Thanks. Tom in Connecticut
@anothergoogleuser 1" of sand to 1.25" clay just lets you know the ratio of sand & clay in your soil. Unless you happen to have soil with the perfect mix, you augment your soil with either additional clay or sand in order to achieve the right clay content. If you have high clay content...you add sand. If you have low clay content...you add pure clay (or find different soil).
I found this interesting, what I would now like to see a video on is what does this percentage tell you? How much sand can be in pottery, a retaining pond?, cob, a kiln? Does having too little sand stop me from doing xyz with it?
One of the best videos I've seen on the subject. I do get contradictory info on this subject though. I just saw a video where they did the drop test and came up with 2 parts Clay to 1 part sand to make the strongest bricks. TO see the video you can search 'Testing soil for clay content' on 'itraveltolearn' channel
If it is sticky and you can make the ribbon test & worm test, then it definitely has clay. It's difficult to say what else is in your soil, though, without seeing your actual shake test...
How can you tell if it would make good refractory? Like fire bricks for furnace. I have read that the higher the alumina there more temperature it can withstand.
I did the jar test? I couldn't see sand line in fact I couldn't see any lines? What did I do wrong? This put off my project 2 years? Not to mention covid
when i do the jar test the top level is not fine as it would indicate a clay layer. if i look close i can look as some grain. however it is stick, it passes all the test and the ribbon. if i remove the top level and dry it it will crack. what do you think it is?
thanks for your great videos. Question: we're using natural local clay in our soil, VERY clay-ey, hardly ANY sand separates out in the water test. Given that, do you recommend one part clay, 2 parts sand for our first layer of cob? And how do we measure the parts? Shoveling out this clay, it's clunky, and a 5gal bucket weighs a ton, and it isn't really "full" in that there are lots of spaces between hunks. Am I being too "particular?" Thanks so much for your help!!
Hi, I'm in New Zealand and I did a shake test it has shown me there is 10% sand 90% clay. Could you tell me how much sand would I have to add to make cob for building a house
So 1 inch of sand to 1.25 inch of clay is good or bad? So cob needs 25% to 30% clay. So in this example this is what %? There is less sand then clay so this cob would not be as strong? I don't understand :-/
you can use a sifter for that. I have a super short video for that here: Sifting Clay Soil I make a sifter just by building a wood table and attaching screening to the table.
Thanks for the upload. I tried to test my soil that way. But I couldn't read the result throught the glass. So I sent 2 samples of my soil for analyses from a competent laboratory. The results are the following : 31 % Clay, 11 % sand and 58 % silt. Can I make mortar out of it ? If you don't answer or if you can't answer I won't be offended and I'll make a test with my soil in order to find out.
try again with less soil in your clay...then you can read it. As for specifics of your lab test, you'd still need to do a field test with your particular soil to see how strong it is. 31% is typically more than enough, however you have a really really high silt content, which can create a very weak material
Thank you. Hum... Yes, silt is bad. I thought initially that what is silt was a mix of chalk and clay.... But not. Bloody silt ! I wonder what to do with it. Anyway, I have the intention to mix my soil with straw and build a small oven and see how it reacts. And if it doesn't work, I'll build a fire bricks oven.
I would still try to make some tests with your soil. It's possible you could augment with a small amount of purchased dry pure clay (from a pottery supplier) and get a mix that is strong enough to use
Ano nymous do all clays have a silt mixture? From what I’ve learned it all depends on the amount of erosion that determines how much of each soil type is in your mixture. I think they had said you could have some without the others.
when you build, you are using a mix with both sand AND clay, so you don't wash the sand out for building or plasters. You just need to know the starting proportions to know how much sand (or clay) to add when building.
buildnaturally yes. i was thinking if you're doing this in mass, you'll need something more than a mason jar. perhaps even large garbage cans or barrels.
buildnaturally Yes, but if I need to add sand and/or clay to the soil I already know the proportions, this means that I still need to have amounts of "pure sand" and "pure clay", right? I think the big issue here is that we don't understand how we can separate one from another and have parts of pure sand and parts of pure clay.
You do this test to determine the proportions in your soil so you know whether you need to augment your soil with clay or with sand in order to get a good mixture for cob, adobe, clay plaster, or whatever you are making. You don't end up separating the ingredients of the soil.
to clarify again, this is not something that you generally do on a large scale, so you are not separating all of the clay from all of the sand in order to build with. You need both sand and clay (proportions vary depending what you are doing with it) to build with. This test just gives you your baseline proportions so you know whether you need to augment with additional clay or sand.
when you say "dirt"...it depends what you mean. If you mean "sand", you generally need the sand in any clay mixture, so you wouldn't want to remove the sand. If you mean "top soil", then you need to dig deeper or in another spot to find an area without topsoil.
silt will definitely settle out before the clay and you will see it stop settling. Then you draw a line and wait for the clay to settle out. Only the clay can stay suspended in the water. Does that make sense? You can feel free to email me a photo, but I'm not sure how much I will be able to tell from a photo. I can't post my email in a youtube comment but you can go to my website buildnaturally-dot-com and you will see my email at the bottom of the page.
paper work Nice feminist catch! How about the countless times I've heard women say they are having babies "when are you having your baby?... I'm having my baby next month...I had him/her when I was 20..." or "any man that cheats isn't worth having... I have a man who spends a lot of time outside..." or "we only have one convenience store in the town where I work..." Is it an announcement of ownership or actually just a harmless choice of words to describe a constituent part of one's life?
Thank you for taking the time to educate us on this very important aspect of cob that I've rarely seen touched on in other videos.
We are using yours and many other ideas on building our cob ovens.
Simply one of the most informational videos about the cob process Ive ever seen!
I am starting plans on building my home in Ayangue, Ecuador. I know the foundation has clay and would love to have a Cob Oven. Its a wonderful view of the ocean, so a lot of outdoor living will take place.....appreciate the demo!
Nice save on the falling jar! And great video!
the exact percentage of sand to clay depends on the type of clay. So I recommend making some test bricks with a variety of ratios and seeing which of the bricks is strongest. Likely your ideal percentage will be somewhere between 15% to 25% total clay content, but I've had clay be as low as 7% and as high as 30%. Make your bricks about the proportions of regular fired bricks (not too skinny in any dimension), then let them dry out, and then break them to see which is strongest.
"total clay content" as in the amount of clay minerals or like the amount of mud/ground material to other ingredients? also is this for the end mixture with straw and whatever in it or just for the mineral content?
The height measurement technique does not account for the fact that the jar is rounded near the bottom. It's best to take a equivalent jar and make your own graduation marks, then translate those marks to the sample jar. Or just mark the sample jar to start with.
nice save!
+River rat cheetah reflexes
My neighbor walked out of his door and the first thing he saw was me holding a brown piece of filth and me smiling because it was holding together.
Good vid, thanks.
A thought about using a cylindrical jar: a more accurate measure might be to empty the jar, fill it to the first line with water and measure that volume. Do the same with the second line and compare the two volumes.
The container's shape becomes irrelevant.
also use the metric system, just coz you then don't have to convert one and 3/8 inch to 1.375 inches or whatever, you can just read it decimally
Thanks, I'll give it a go as soon as the weather fines up. I'm really looking forward to seeing how this turns out. I've got a few projects I would like to complete using cob, this is going to be interesting... Thanks again for your help.
the actual amount of clay that is ideal depends on several variables. 1st is the actual type of clay. Different clay absorbs different amount of water, thus swells different amounts, thus gets stickier or less sticky. That said, the highest percentage of clay I have ever used is 30% (lowest is 8%, to give you a sense of the variation). My gut instinct is that 2 parts clay is way too much and it will shrink and crack a lot (especially if you are building a thermal mass layer without straw).
I guess that many people (like me) think that just after the jar test, natural builders have a way to separate clay and sand in two batches. I still have some doubts about the process of making cob... in most tutorials they already have the sand and clay separated in batches, and then show you how to mix them with straw. But if I want to extract them from my own soil I should do this jar test. Let's say my soil is 60% sand, 20% silt and 20% clay. What I should do after I discover it by the jar test? That's what I still don't understand and for sure many people as well.
This test allows you to know the proportions in your particular soil. That becomes your baseline, so you know if you need to augment your soil with additional clay or with additional sand in order to get a good, strong, non-cracking mixture for clay materials (cob, adobe, clay plasters, etc.) You don't need to separate the clay from the sand in all of the soil, you are just adding sand or clay to adjust your existing proportions.
+buildnaturally Is there an allowable measure of silt that would work in cob? I've read that silt in cob is a no no and having to dig it all myself, I'm concerned I might need to over complicate the process to remove the silts. Any tips or advice?
+Michael J generally up to about 10% silt is okay...not ideal...but ok
Melissa Webster your question is still unanswered... What should you do ?
you should fill it with other material, either store bought or found somewhere else, until it's the ideal mixture for you. i suppose you also could wait for the sand to settle (around 10-30 seconds) and then separate the two, same goes for silt although i don't know how difficult that is, since i haven't searched for an answer yet
also read the top comment made by the channel if you need more info. there's a lot more detail there. it's apparently not too complicated if you just try it out and see what works best
I been wanting to build a pond on my property and its over 60% sand. Today I dug another 6ft hole about 50 ft away from creek and appears to look better just waiting for the jar contents to start settling. I believe I may end up moving the pond away from the creek to get the better clay content and then adding another 3 or 4 inchs of clay on top. 20yards of clay is $150 delivered 15 miles from site and I wanted 130 yards to get a good seal.
have fun building your oven & cooking in it!
Thank you for your answer. Please post more videos as you progress.
With greetings from Shiraz, Iran
@anothergoogleuser As an example...take our shake test as approx 1 part sand to 1 part clay (for ease of math), that is a 50% clay content. You want 25%, so you need to add 1 part sand for each 1 part soil, which will give you a final mix of 3 parts sand (2 from the pure sand and 1 from the soil) to 1 part clay (1/2 the makeup of the soil) or 75% sand and 25% clay. Then I recommend making test bricks to find out the exact percentage of your clay that will be strongest.
Thanks, I needed to figure out how to detect clay in sand/dirt because I am making a clay battery, and I heard that clay holds more microbes then dirt does.
3hornthrasher are you attempting to make the same type found in Egyptian digs?
You show two lines. How do you know where to draw the bottom line, if the contents are still settling? I don't know how to distinguish the "sand" layer top from the beginning of the clay content section. Thanks. Tom in Connecticut
Thank you and, nice catch lady.
lol, self support "a load". The turd test. Very informative. I have some growing up to do.
Nicely explained thanks
@anothergoogleuser 1" of sand to 1.25" clay just lets you know the ratio of sand & clay in your soil. Unless you happen to have soil with the perfect mix, you augment your soil with either additional clay or sand in order to achieve the right clay content. If you have high clay content...you add sand. If you have low clay content...you add pure clay (or find different soil).
I found this interesting, what I would now like to see a video on is what does this percentage tell you? How much sand can be in pottery, a retaining pond?, cob, a kiln? Does having too little sand stop me from doing xyz with it?
Very nice information for our house project . . . We have children so I would really appreciate knowing how you get your white top clean . 🤗
One of the best videos I've seen on the subject.
I do get contradictory info on this subject though. I just saw a video where they did the drop test and came up with 2 parts Clay to 1 part sand to make the strongest bricks. TO see the video you can search 'Testing soil for clay content' on 'itraveltolearn' channel
If it is sticky and you can make the ribbon test & worm test, then it definitely has clay. It's difficult to say what else is in your soil, though, without seeing your actual shake test...
How can you tell if it would make good refractory? Like fire bricks for furnace. I have read that the higher the alumina there more temperature it can withstand.
I did the jar test? I couldn't see sand line in fact I couldn't see any lines? What did I do wrong?
This put off my project 2 years? Not to mention covid
Thanks you
when i do the jar test the top level is not fine as it would indicate a clay layer. if i look close i can look as some grain. however it is stick, it passes all the test and the ribbon. if i remove the top level and dry it it will crack. what do you think it is?
thanks for your great videos. Question: we're using natural local clay in our soil, VERY clay-ey, hardly ANY sand separates out in the water test. Given that, do you recommend one part clay, 2 parts sand for our first layer of cob? And how do we measure the parts? Shoveling out this clay, it's clunky, and a 5gal bucket weighs a ton, and it isn't really "full" in that there are lots of spaces between hunks. Am I being too "particular?" Thanks so much for your help!!
you would need to make test bricks with your soil to find the right proportions...every type of clay is a bit different.
Hi, I'm in New Zealand and I did a shake test it has shown me there is 10% sand 90% clay. Could you tell me how much sand would I have to add to make cob for building a house
So 1 inch of sand to 1.25 inch of clay is good or bad? So cob needs 25% to 30% clay. So in this example this is what %? There is less sand then clay so this cob would not be as strong? I don't understand :-/
I really want to harvest clay in our area. But I'm having difficulty distinguishing clay and silt :'(
@BarbaraMParis Try digging deeper, if you haven't already. sometimes the clay is a couple feet down...
Thanks! That is helpful
Thanks a lot
Very good you just need to wash the tee-shirt now , thanks.
awesome info. Thanky ou!
I have very little clay... Now what? Add clean cat litter?
I have mainly red clay here in eastern TN with a lot of shale rock in it how is the best way to remove rock from clay
you can use a sifter for that. I have a super short video for that here: Sifting Clay Soil I make a sifter just by building a wood table and attaching screening to the table.
Thanks for the upload. I tried to test my soil that way. But I couldn't read the result throught the glass. So I sent 2 samples of my soil for analyses from a competent laboratory. The results are the following : 31 % Clay, 11 % sand and 58 % silt. Can I make mortar out of it ? If you don't answer or if you can't answer I won't be offended and I'll make a test with my soil in order to find out.
try again with less soil in your clay...then you can read it. As for specifics of your lab test, you'd still need to do a field test with your particular soil to see how strong it is. 31% is typically more than enough, however you have a really really high silt content, which can create a very weak material
Thank you. Hum... Yes, silt is bad. I thought initially that what is silt was a mix of chalk and clay.... But not. Bloody silt ! I wonder what to do with it. Anyway, I have the intention to mix my soil with straw and build a small oven and see how it reacts. And if it doesn't work, I'll build a fire bricks oven.
I would still try to make some tests with your soil. It's possible you could augment with a small amount of purchased dry pure clay (from a pottery supplier) and get a mix that is strong enough to use
given all soil is mixed as a percentage? Whats the percentage and how much sand etc would we need to add????????
that depends on your clay soil and it depends on what you are doing with the clay. this video is just showing how to test the soil
If you're making adobe, it's helpful to know how much clay is in the soil, or they'll fall apart.
So the question is.. WHERE'S YOUR SILT?
Ano nymous do all clays have a silt mixture? From what I’ve learned it all depends on the amount of erosion that determines how much of each soil type is in your mixture. I think they had said you could have some without the others.
I can't stop giggling about the 'load'. Rofl!
It's a load alright... XD
@sigikoko Thanks, I will do that :)
so when you're getting the sand out and getting the clay out do you use 5 gallon buckets? I couldn't imagine building something and using mason jars.
when you build, you are using a mix with both sand AND clay, so you don't wash the sand out for building or plasters. You just need to know the starting proportions to know how much sand (or clay) to add when building.
buildnaturally yes. i was thinking if you're doing this in mass, you'll need something more than a mason jar. perhaps even large garbage cans or barrels.
buildnaturally Yes, but if I need to add sand and/or clay to the soil I already know the proportions, this means that I still need to have amounts of "pure sand" and "pure clay", right? I think the big issue here is that we don't understand how we can separate one from another and have parts of pure sand and parts of pure clay.
You do this test to determine the proportions in your soil so you know whether you need to augment your soil with clay or with sand in order to get a good mixture for cob, adobe, clay plaster, or whatever you are making. You don't end up separating the ingredients of the soil.
to clarify again, this is not something that you generally do on a large scale, so you are not separating all of the clay from all of the sand in order to build with. You need both sand and clay (proportions vary depending what you are doing with it) to build with. This test just gives you your baseline proportions so you know whether you need to augment with additional clay or sand.
not gravity but buoyancy or density
The camera is 3 times better than an Android!
how do you know how mutch top soil is mixed with the clay?
you need to use soil that does not have high organic content...you want just clay and sand (organics are light and will float in the shake test)
buildnaturally I was referring to dirt vs Organix
what if i have a lot of dirt. like half clay half dirt
how do i get rid of the sand?
when you say "dirt"...it depends what you mean. If you mean "sand", you generally need the sand in any clay mixture, so you wouldn't want to remove the sand. If you mean "top soil", then you need to dig deeper or in another spot to find an area without topsoil.
I think my poo must be clay !!!!!.
Mr Hankey…
LOL There goes the nice clean shirt at 1:38 !
Excellent, sadly I just have a thin layer of good clay :(
So, what are you going to do? Add cat litter?
silt will definitely settle out before the clay and you will see it stop settling. Then you draw a line and wait for the clay to settle out. Only the clay can stay suspended in the water. Does that make sense? You can feel free to email me a photo, but I'm not sure how much I will be able to tell from a photo. I can't post my email in a youtube comment but you can go to my website buildnaturally-dot-com and you will see my email at the bottom of the page.
'Solution' and 'suspension' are not the same thing.
Dennis Dekker can you clarify what they are 😲 their differences
hello. if you have an email I can send you photos. as i said its not that dusty particles is looks a combination of silt -clay
Good for using soil,not drit.
Worm? You made a turd lady!!!
wish I could have a woman who likes dirt
That's the problem right there. Women are not property, you can't HAVE a woman.
paper work Nice feminist catch! How about the countless times I've heard women say they are having babies "when are you having your baby?... I'm having my baby next month...I had him/her when I was 20..." or "any man that cheats isn't worth having... I have a man who spends a lot of time outside..." or "we only have one convenience store in the town where I work..." Is it an announcement of ownership or actually just a harmless choice of words to describe a constituent part of one's life?
Oooh that looks so gross.