Nora,...
-these are inside walls?
the walls normally, unless the structure of the clat layers is to show, have a bamboo lattice on the wall edge that acts as stucco wire. This is then parged over with lighter, more viscous clay mixture, which could be colored, mixed with grasses, various treatments to reach the ideal that you would like to have. Or painted over.
... it is usually easier to call a professional, and this is part of this forum, mud walls...

you're intending to do this yourself? not really hard, just knowing the right preparation from onsite information, how dry, how wet to make it first for adherence, etc. what type + consistency of clay bonds with what...
edzard

Hi Nora ^-^ .
what troubles you are get into ?
Clay is mixed with lime and rice straw. where you are, soil around your area is probably not good for mudwall. too sandy. bamboo latice is about 5cm square, and use yadake, shino dake, which has thin wall and straight cane. 3 years old bamboo is good for the latice work.
Mud wall is out of Gardner's teritory. I have a child hood friend who is "Sakanya" mason and I can also ask to Dr Onoe who teachs Japanese treditional constraction at the Univercity.

Ask your mom for a check and ask to your inlaw an advice if they know someone you can trust.^-^ . I have not hear from your mom for a while. please say hello for me

Edzard made excelent sugestion. If you still want to do your self, let's us to know. ..................mike

The only thing I can think of in western building would be to look up either daub and wattle construction or cob to get the right kind of mud/clay that has a good stickyness and low shrinkage.
Any sources that you run across of the JN methods in English I would love to see.

In the interest of improving my own straw/clay wall construction skills, I spent some time talking with museum workers at the "Nihon Minka-En" in Kawasaki, near Tokyo, two weeks ago. This collection of old houses from all over Japan is an excellent resource for learning about construction technique and design issues. All the buildings were taken apart and rebuilt on the site, so traditional craftsmen are present that know the methods first hand. You could probably learn a lot about clay wall construction by talking with people there. Most of the buildings have some variation on this technique and all are constantly maintained and some are being rebuilt. What I learned includes: there are multiple layers, with different reinforcing (bamboo lattice or straw),the top layer is often almost pure clay/lime in some formal construction, and that the quality of the natural materials are critical.

Good luck

Thanks for the clues so far!

Yes, I want to do this myself. The quote I received from a professional was 60,000 yen for the one room. Yikes!

I'm going on an info-hunting mission today... Will report back. I've been told to scrape down the walls, then add more clay. Hopefully I'll find out what kind of scrapers to use (and how) and where to buy the clay mix... then how to apply it.

This should be useful info for the person who wants to build a tea-house, too. The ones I've been in all have clay walls.

Sorry, Yama, my in-laws are hopeless for DIY projects. They make great ume-boshi, though!

Hi Nora
This book may help you " Nihon kabe no hanashi" by Yamada koichi Kashima shupankai. "kashima" is same as kashima constraction company. you can find many related books in Amazon.com /Japanese.

I have detail of kabe/wall constarction. it is for professional .
"mokuzo kenchiku gijutsu zukai" by Otsuka Tsuneo publisher /Rikogakusha
aslo" mokuzokenchiku no gijutsu " by Onoe Koichi/ Rikogakusha. I do know Onoe sensei personaly.

Check Rikogakusha's publication.
above mentioned book is purchesed 20 some yeras ago. I am for sur that Rikogakusha may have more recent books.

when inlaw are not much help ask your mom for help ^-^ . chck is easy to send .
Will you ask youe inlaw if she can make extra Umeboshi for me. I am happy to pay. My mother broken right hand last week and she is getting old. I cannot ask my mother to make Umeboshi no longer.
If you are intrested in the contents of book. send me email, I will copy and send it to you. .................. mike