Thread: Mud, bamboo and alternative building materials

Originally Posted by Dan

The problem is that it's just me, part-time, so progress is limited.

I'm assuming the locals haven't been queuing up to help and learn something new?

^ Ha ha! Not exactly, no. They all stop, say hello, have a good gawp and then, I'm sure, report back to the family something along the lines of "That foreigner's fucking nuts. You won't believe what he's doing now..." Still, I have high hopes that once it's all finished, and assuming my woeful efforts don't collapse, I may be able to change a few pre-conceptions...or maybe not.

How's the bamboo working out?

I think one hurdle would be how cheap those little red blocks (that are currently used) are. Regardless sustainable or cool your adobe blocks are in order to sell them to the local populace the price would have to be extremely low.

I'm not sure about that. I think there's a market for earth building amongst a section of the middle class here. In the last few months, I've met a few Thais (educated to post-grad level and/or foreign educated) who've expressed an interest in building with earth, or who are actually doing it, and they're not doing it because it's cheap but because they find the idea attractive, in much the same way as middle class bell-ends like me find it attractive.

Thanks, interesting links..I have found Adobe Madre...cant post links yet, but they have moulds that include hollows for reinforcing rods and conduits as well as a scaffolding system.simple slipform lay ups for the adobes.

Not sure about the commercial aspect, I guess most interested parties are keen to self- build an environmentally sound dwelling for as little as possible and enjoy living in it rather than buy one done for them. But if you build something really special there could well be interest. My own project is a shop, a house and some guest cabins for a b&b on our land up county, the cabins could of course be interesting mini projects in different techniques. Gotta put a huge wall up which is too expensive with conventional means.I will need thousands of blocks.

Investing in a press or slipforms or suchlike is actually going to save money, or work out the same (as conventional), but I get to own some nice kit too. Might well go on an Adobe course. Cheers, PP.

^ In case you're tempted to go to Pun Pun (up near Chiang Mai), I'd think again; I went there before Christmas and had - and I'll be generous here - mixed feelings about it. A lot of the adobe building here seems to be done by hippies who really don't seem to know much more than anyone else. I'm not sure where you are but there are plenty of people doing it in the States who do seem to know what they're doing so, if that's an option, I'd consider it over doing a course in Thailand.

Originally Posted by Dan

I think one hurdle would be how cheap those little red blocks (that are currently used) are. Regardless sustainable or cool your adobe blocks are in order to sell them to the local populace the price would have to be extremely low.

I'm not sure about that. I think there's a market for earth building amongst a section of the middle class here. In the last few months, I've met a few Thais (educated to post-grad level and/or foreign educated) who've expressed an interest in building with earth, or who are actually doing it, and they're not doing it because it's cheap but because they find the idea attractive, in much the same way as middle class bell-ends like me find it attractive.

I would tend to agree, there's an increase in green home interest among the middle class, especially for the weekenders. A big advantage here is the cheap labor, however this is offset by the lack of skills. Soil and other ingredients can be bought easily, so I would tend to think adobe could be very cheap if you had the right team doing it, which explains all the earth builders popping up.

There seem to be some ppl doing it here that know their stuff. I'll check that project again and see if I can get some details. Despite the fact the project is set up to encourage ppl, the guy running it was a little short on details, however I think they do seminars. They have a website ศูนย์à¸[at]ูมิรัà¸�ษ์ธรภ£à¸¡à¸Šà¸²à¸•à¸´ - Home Maybe someone could call them to see if they run courses?

^ Don't get me wrong, I'm sure the best courses are to be found abroad, it's just that sometimes what their teaching may be difficult to apply here.

In general Thais aren't that good at passing on knowledge. Sometimes they want to be secretive and sometimes it's because they're just not good teachers.

There's interesting stuff going on in South Asia, for a donation I'm sure they would be willing to pass on their knowledge. The pictures below is from Nepal

i would also agree about punpun and the other communities around chiangmai they are very hippy-run communes for permaculture rather then knowledgeable builders of natural vernacular architecture!!!

However if you ignore that they can give you extensive knowledge about types of materials and where are the best places to get these from, if you email them its free and as with all free info you can take or leave it (ive set myself up there)!

I will building soon in mae rim, chiangmai.....

Originally Posted by benlovesnuk

I think your clay content is too high (though i know you seem to have ruled me out for any advice on this subject)

I'm happy to take advice from anyone who is in a position to give it. Why do you think I have too much clay? What problems will I have?

Can anybody who know about mud comment on the technique being used in the pics below. What type of mud mix would be a good? What's the chances of it cracking and looking shite? I'm looking at doing a bungalow similar to this and am wondering if it's better to just go with cement mortar.

^ The blog doesn't allow hotlinking, so most of us can't see the photos, I'm afraid.

Your picture seems to have gone awol but if you want to test for shrinkage, you need to make a box, put some wet clay in and let it dry. This page (Farm structures ... - Ch3 Building materials: Earth as building material) gives an indication of what to do. I haven't bothered doing exactly this because I had the mould for my adobes so I made a set of 100% clay (my sub-soil) blocks to see how bad the shrinkage was. As I'm on kaolin, none of the blocks had any cracking at all. Unfortunately, I've not had experience of mud plaster so I can't really give too much advice on the mixture required.

Edit: I think I sent you a link for Building with Earth by Gernot Mike (on scribd.com). That has, I think, a section on earth plasters. If I didn't, let me know and I'll see if I can find it.

OK, hopefully these ones will work better. Looks easier than making the bricks and Thais could adapt (maybe?) because they're used to rendering. There are variations on the methods, was popular in Sth America and is making a bit of a comeback there.

In Asia similar things are being done, but they recommend using cement, so my guess is it's prone to cracking.

Other than the obvious risk of termite infestation, I can't see any problem with that, or why cement would be preferable to earth. If it's got the wide overhangs and it's on a stem wall, earth would, I think, be fine. Adding sand or organic fibres to your clay will reduce the risk of cracking. Also, working in several thin layers will do the same. Why not make a small panel, plaster it with earth and see what happens? It shouldn't take long.

Originally Posted by Dan

Other than the obvious risk of termite infestation, I can't see any problem with that, or why cement would be preferable to earth. If it's got the wide overhangs and it's on a stem wall, earth would, I think, be fine. Adding sand or organic fibres to your clay will reduce the risk of cracking. Also, working in several thin layers will do the same. Why not make a small panel, plaster it with earth and see what happens? It shouldn't take long.

Where did you get your info or understanding that termites like earth buildings, is this personal experience or hear say, internet etc etc????

Its just that From quite a wide source i understand that termites have no interest in adobe or cob for any purpose, especially compacted soil mixed in this fashion its simply not a food source or even possible for them to generally borough through! I believe termites that come from the ground can be stopped by adding a sand barrier i think of about an inch thick when compacted down as they cannot get through.

Secondly termites that fly which there are some in chiangmai, have to be dealt with in other ways, but like i said im pretty certain that they have no interest in adobe cob or any other earth mix for building....only wood!

One last thing traditionally, as has been done for over 500 years in devon though it fluctates depending on what was applicable in the region in the earth at the time, the mix is typically 20% clay 80% aggregate, the adding of straw or coconut hairs or whatever is added after...this should give a pretty strong sturdy mix that should not buckle when rolled in a ball and dropped from shoulder height!

Originally Posted by Dan

My experience with adobe is it's great.

That's interesting - can you expand? Do you have construction experience with adobe? Like a said a few posts up, I'm building - slowly - a 4 x 3 metre test structure to try to see how things work out so I'd be grateful for any advice you could give. I've just been making test blocks to see what mix of clay/sand/rice husks/straw/cement works best but it's hard getting enough time in (and making the adobes is very time consuming).

Some of my miserable efforts (the latest lot actually aren't too bad - 8 clay: 5 rice husk: 2 sand: 0.5 cement and mixed fairly dry):

your clay seems high in comparison to sand, as i said this would be my first mix then add the husk not sure you need any cement upto you, the sand should not be beach sand the more coarse the better rough shapes hold together better. Get your local woody to make the form out of wood and test with the different percentages of mix. You can get straw probably just as easily as coconut husk really anything goes but straw is in my opinion a better holding agent to clay and sand and also more common to the techniques ive used!

The techniques you mention are still relatively unreferenced and only hit the last 30 years or so in more mainstream use as a viable method for cheap, strong natural building. The use of bamboo is obviously proven i think wattle and daub would be me my choice using the bamboo as would have been the wood timber frame of old builds. Then using a weavethrough your uprights you'll create a board to daub on. clay water and hoarse hair, husk straw to add to fill in.,very lightweight and strong.

cant wait for everyones finshed plans

Originally Posted by benlovesnuk

Where did you get your info or understanding that termites like earth buildings, is this personal experience or hear say, internet etc etc???? Its just that From quite a wide source i understand that termites have no interest in adobe or cob for any purpose, especially compacted soil mixed in this fashion its simply not a food source or even possible for them to generally borough through!

a. Smithson's picture shows a bamboo building. Termites have been fairly interested in the bamboo I have lying around on my land so I think there's a fair chance they might be interested in his.

b. Termites can easily pass through adobe or cob. Rammed earth is - I believe - different. At Pun Pun they have had to knock down adobe buidlings because of termites. The ternites are obviously not interested in the adobe itself but they tunnel through it to things they are interested in (window frames, books, etc), much as in any regular house.

I believe termites that come from the ground can be stopped by adding a sand barrier i think of about an inch thick when compacted down as they cannot get through.

It's true that termites can't get through some sand but it has to be a certain size (too big to carry, too small to provide gaps through which they can move), and a lot thicker than an inch.

The point about the clay is that to a large degree it depends what type of clay you have and which is why it's not necessarily very useful saying "you don't have enough sand." My clay is notably non-expansive so my adobes don't suffer from cracking (I've already made 100% clay test bricks which are now almost completely dry and they haven't had any cracking at all.) Following recipes, particularly recipes from a country with a very different climate and geology, is not the best way forward. This will no doubt become clear to you when you start building.

Originally Posted by Dan

Originally Posted by benlovesnuk

Where did you get your info or understanding that termites like earth buildings, is this personal experience or hear say, internet etc etc???? Its just that From quite a wide source i understand that termites have no interest in adobe or cob for any purpose, especially compacted soil mixed in this fashion its simply not a food source or even possible for them to generally borough through!

a. Smithson's picture shows a bamboo building. Termites have been fairly interested in the bamboo I have lying around on my land so I think there's a fair chance they might be interested in his.

b. Termites can easily pass through adobe or cob. Rammed earth is - I believe - different. At Pun Pun they have had to knock down adobe buidlings because of termites. The ternites are obviously not interested in the adobe itself but they tunnel through it to things they are interested in (window frames, books, etc), much as in any regular house.

I believe termites that come from the ground can be stopped by adding a sand barrier i think of about an inch thick when compacted down as they cannot get through.

It's true that termites can't get through some sand but it has to be a certain size (too big to carry, too small to provide gaps through which they can move), and a lot thicker than an inch.

The point about the clay is that to a large degree it depends what type of clay you have and which is why it's not necessarily very useful saying "you don't have enough sand." My clay is notably non-expansive so my adobes don't suffer from cracking (I've already made 100% clay test bricks which are now almost completely dry and they haven't had any cracking at all.) Following recipes, particularly recipes from a country with a very different climate and geology, is not the best way forward. This will no doubt become clear to you when you start building.

I believe you are right, i would not be surprised to find out that they can enter crack lines more easily in adobe then cob and as you mentioned rammed earth. At punpun i dont think they concern themselves too much with active pest control or prevention from my contact with them they do not apply similar building regulations or methods as thourougly as most would want - as you say they are more hippy and open natured towards their lifestyle and choice of building.

Sand can help prevent intrusion from termites although not widely field tested has shown more complication then just pumping chemicals into the ground. But where possible natural prevention in materials for pests and also in design and living would be preferable where ever possible for myself. There are some quite good reads on the internet!

Im glad that you have taken the plunge with some testing, i hope you havent read too much into my other posts beforehand there is sometimes a neccessity to facilitate caution when writing on these sites. Although my posts seem garbled and attacking their was a genuine though now seemingly unneccessary reason.

I completely understand and admire those that do rather then say, and then afterwards share - practical knowledge is unquestionably the key to building in this unreferenced difficult method. I once again wish you well in your building and also smithson for putting something different into action to show that vernacular architecture has beauty and meaning in this very generic concrete building craze.

good luck to you both!

Dan, your comment about different climate and geology intrigued me, i had a quick look and found this about a complimentary building system that is half adobe half rammed earth - because of your initial interests i thought i would highlight this to your attention.

I am confident you might have heard of this before, i have not, and maybe thought we could discuss it further?

Compressed earth block - Wikipedia, the free encyclopedia

some typical examples of its advantages over most other techniques:

Other advantages:

• Non-toxic: materials are completely natural and do not out-gas toxic chemicals
• Sound resistant: an important feature in high-density neighborhoods, residential areas adjacent to industrial zones
• Fire resistant: earthen walls do not burn
• Insect resistant: the walls are solid and very dense, discouraging insects
• Mold resistant: there is no cellulose material - such as in wood, Oriented Strand Board or drywall - that can host mold

hope to hear your your opinion on the matter?

Look at the first and second pages of this thread. I looked into CEBs but decided against it. They have a lot of advantages over adobe - principally that they're stronger and more stable and uniform - but it seems that they're also more difficult to make in that the mix and moisture levels have to be much more precisely managed and you have to screen your materials much more carefully. You also have the cost of investing in a press (or buying blocks), which doesn't really appeal to me as I can't see myself building more than one house.

I did some drop tests on my last set of adobes today. Interestingly, the pure clay, the clay/rice husk/sand, and the clay/rice husk/sand/cement all seemed to have equal strength - all only broke slightly on the corner when dropped from chest height (which is what they should do). The only difference was when I jumped on the clay, which shattered, whereas those with rice husks were unaffected. I spent the day making a new set of test blocks (16 clay, 5 chopped straw, 5 rice husk, 4 sand). They came out looking pretty good but mixing straw into clay is a bastard compared to the rice husks.

Sorry completely missed your entry!?!

What are you proposing to use as a mortar?

what size are your bricks, will they be completely uniform all over in size?

How much mud do you think youll need to complete the house?

Have you considered just building to the first floor with adobe and then by frame (either wood bamboo) and then wattle and daub? or do you have too big a termite problem?

will you build the roof out of adobe or are you going to be using something else?

cheers

Wondering how bamboo will hold together after 10 years of moisture/drying cycles. What do you figure the strength might be?

I'm no engineer, but this thread has provided more than a few laughs.

Why don't the metropolitian authorities of Bangkok, KL and Singapore build their bridges and high rises and landmarks from bamboo?

Perhaps they're missing something.