[THE SHOW: Kyoto Walls: Elegance Molded from Earth
Airing on July 7, 2016, on NHK World, Core Kyoto’s classical Kyoto walls episode will include scenes of this nakanuri finish application on site. The following blog entry describes how the plaster was created, and about the application. Depending on how they edit the footage shot on site, you will get to see a pro in action with this very plaster, saving me from pretending I can take it to the finish. The show will be available online for a month. (If you happen to get the NHK World channel, it will show four times on Thursday, July 7th, Japan time.) It is very exciting. The channel airs to 170 countries, and 200 MILLION households. Maybe seeing a white girl speaking Japanese, with English subtitles, will tickle people’s attention. Maybe they will remember this elegant earthen option when refinishing the walls of their own homes. I hope you and your friends watch! I know it will be fascinating.]
Nakanuri is typically just the same as a “brown coat,” meaning, it’s the plastered application before the finish plaster, or the substrate to the finish plaster. Depending on the structure and the budget, though, it can sometimes be the finish coat itself. In that case, it is often prepared especially to serve that purpose. I was able to document the process while Asahara Ichiro and I prepared the two different nakanuri finishes used for the residence that became a special place to me: the location where the NHK World film crew took footage of my mentor, Ichiro, pumping up the scene for them to film the odd American girl that’s hooked on this classical Japanese plastering stuff.
So, without further ado…
TWO CUSTOMIZED PLASTERS
Clay. Isn’t it convenient? The clay gets delivered like this. We made two different plasters: one with clay from Awaji-shima, an island south of Kobe, and another from Aichi prefecture.
Straw. Another convenience, the straw is processed and delivered like so. (Further details to follow.)
Sand. All these bags of sand live outside in organized stacks. Some stacks are processed, others are not. I basically spent all day here, processing (you’ll see that later).
Prepping the materials
Sifted. I can’t remember the mesh size, but you can tell, very fine. The sifter is a round, hand-shaken thing, about the size of the top of a bucket. (I think the mesh was 5-rin, which translates to about 1.5 millimeters, or about 0.06 inches.)
After sifting, the clay gets measured into a measuring bucket that has the liters marked up to 10.
See the round thing in the square thing? (where’s my English?) That’s the same shape as the sifter that was being used for the clay (just for perspective purposes). For our plasters, we used two different meshed sand. One was 1bu2rin (or 3.6 mm / 0.134 inches), the other was 1bu (3 mm / 0.12 inches). I’ll explain later.
If this were my own outfit, I would take more cautious measures to keep the sand dry, because sifting wet sand is a ….(fill in as you wish with a negative connotation.)
Above, the finished product, below, good pebbles for using in the bottom of planters for drainage for your balcony garden : )
No extra work necessary, it comes in bag like this. For the straw, we also used two different “sizes.” You’ll see (maybe!).
This one, from one company.
This one, from another company. See the difference?
Mixing the materials (the photo on the left tells the most)
Recipes. The two on top use the clay from Aichi, and the two on the bottom use the clay from Awaji. NAKANURI IS ALWAYS APPLIED WITH TWO PASSES. On the left is the recipe for the first pass, with the larger-screened sand. On the right is the recipe for the second pass (the finish surface, in this case), with the smaller-screened sand. The numbers with gramage are referring to the weight of straw added to the mix. The second pass got both varieties of straw, and quite a bit more of it than the first pass’s mix. Why? You’ll have to ask Ichiro, he knows everything.
Have your tender bring you water and sand while you keep the machine going and measure straw. This mixer, like an Imer, is very powerful, and a good friend.
Don’t forget to add water during these steps. The straw will continue to soak up water after you unload the mix, so adding a little extra is a good measure. How much water? depends on the day and the opinion of the person mixing.
The good friend.
Loading the materials
This truck is a great design. I want one. The fabric side folds down, the whole side folds down, and of course the back end folds down. And of course it’s a hydraulic dump truck.
The two different clays were two different colors, which referred to as “red” and “yellow”. This is the “red,” first pass on one side, second pass on the other. We organized the truck so we knew exactly which ones were for the first and second pass for each of the colors. P.S. Don’t let me forget to tell you about how the colors change, and quick!
THE APPLICATION / ON SITE
Nakanuri always goes on in two passes with a jigane trowel. Here, being the finish, it gets a little extra attention. After the second pass is applied, a 0.4mm thick hanyaki trowel is used to give the right texture. The crew aimed to barely expose the straw, while it lay at the surface in “just the right way,” a soft way. Note: no compression.
Big hallway wall, still wet
This was an old house, so most of the substrates that were being plastered were arakabe, or scratch coat of clay/straw over bamboo lattice work. That means you loose your moisture much quicker than going over something like drywall, which is not so absorbent. This crew doesn’t even think about keeping the windows closed to keep from loosing moisture to the wind, the way I’ve done for finishes over strawbale walls in the U.S. They just open the windows right up and welcome in the cool breeze. They work with that much speed and confidence. We didn’t use tape on this job except for the walls that were finished with lime or lime-clay.
Each corner of the arakabe had “higeko” nailed in. “Higeko” is a little brad nail that has a length of fibery hemp tied to it, that gets laid into the first pass in a “V” shape. It prevents the earth plaster from shrinking away from the wood. You have to make sure to knock/press the head of the nail into the arakabe wall, or you risk nicking your trowel.
As the plaster dries…
Brightness. It’s hard to tell, but the plaster in the foreground is the “yellow,” and in the background is the “red.” They’re hardly different, but just enough to give an essence of variety to the home.
Can you appreciate how tricky this cubby must be to plaster? Going around that shelving… Here, Maru-san is making sure he can take enough time to hit all the details without loosing moisture, using a small brush to wet down each little edge. As a tarp he is using a “mushiro,” the stripped off surface of a tatami mat that we can get from tatami refinishers. Reused! It’s our standard tarp indoors. Also note he is wearing “inside shoes.” We have to change our shoes at the entrance, as per Japanese custom.
Even the back of the upper-pony wall was plastered. The cubby to the left (not photoed) had a double-upper-pony wall. Maru-san is the go-to for the walls that no one else wants to plaster.
So steep! Yes, carried many buckets of mud up these stairs. yes, the walls on either side were plastered over arakabe.
First floor hallway adjacent to backyard garden.
Kitchen wall, pigmented lime.
Lime-clay “asagi-tsuchi” or blue clay, entry way.
Kitani-san plastering the lime-clay. Lights are always used to help find all the areas that need another little bit of material before making the final passes with the 0.4 honyaki trowel. (Isn’t it interesting how the plaster looks grey/green wet, and dries blue?) The blue styrofoam over the wooden posts protects their finish during the restoration.
New ductwork was put into the kitchen. I tried my hand at doing the nakanuri finish, but each time I lost to the receding moisture, and Kitani-san had to save me. The filler, on the outside around the ductwork, is the only “finish” that was my own in the whole house. Visible from the street! This photo was taken just after application. I hope that when the plaster dried the patch-work was not so obvious…