Kominka

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Zasso Nouka
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Re: Kominka

Post by Zasso Nouka » Mon Aug 22, 2016 6:43 am

What's the advantage of a hard packed dirt floor over a concrete one ? Is it practical or more aesthetically pleasing ?

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Re: Kominka

Post by xxxxtom » Mon Aug 22, 2016 11:49 am

Gday Brett,
Is your kitchen on the same level as the doma?
Does your doma lead into the kitchen?
If so what surface is the kitchen floor?
Do you know what wood treatment (shibukaki?) kominka Windows and frames were traditionally treated with or are they left natural?
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Re: Kominka

Post by BrettRas » Mon Aug 22, 2016 6:45 pm

Zasso Nouka wrote:What's the advantage of a hard packed dirt floor over a concrete one ? Is it practical or more aesthetically pleasing ?
It has both aesthetic and practical benefits for a kominka, in my opinion. Aesthetically, it blends in with the other natural elements and colors of the house very well. On Ojika, the volcanic soil is red, so the floor has a nice crimson color which looks nice with the browns of the floor beams and boards.
The earth of the floor compliments the earth walls, paper on the shoji, etc. Everything is made from simple natural materials, ideally able to be procured near the place where the home is built.
This plays into the practicality of the earth floor as well. Repairs, alterations, etc. can be done with materials readily at hand and acquirable for very little money. Of course concrete is easy and cheap to get ahold of these days but it's not as easy to repair a chip or crack in a nicely finished floor. And those fancy concretes and self-leveling compounds and whatnot have their share of unnatural additives these days. Not the end of the world I suppose, but not something I'm interested in using when I can avoid it.
Also, moisture management. Kominka need to breathe, and in general, concrete hinders that process. What you often see with these concrete entryway floors is that where they end and they meet wood beams for example, the moisture finds its way there and will damage the wood more quickly than if it were more open and allowed to release moisture elsewhere as well. Concrete walls can cause similar problems.
The concrete also can cause a headache with termites. Rather than finding a termite tube coming up from a crack in the concrete, and being stuck with no access to the ground below for remediation, you can have direct access to better remedy the situation.

Sorry I'm starting to rush and ramble my response here, dinner is mostly ready and the shichirin needs my attention! :)
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Re: Kominka

Post by BrettRas » Mon Aug 22, 2016 7:19 pm

xxxxtom wrote:Gday Brett,
Is your kitchen on the same level as the doma?
Does your doma lead into the kitchen?
If so what surface is the kitchen floor?
Do you know what wood treatment (shibukaki?) kominka Windows and frames were traditionally treated with or are they left natural?
Cheers
Hey Tom,

The kitchen is raised up from the doma with a wood plank floor. It's not the original arrangement, and was probably changed many many years ago. The kamado that is here now certainly isn't the original. Nor the sink. It would have been in the low doma space.

Do you mean the exterior surface? Could have been a number of things depending on the area of Japan and the timeframe. Of course older kominka built before the widespread use of glass would have had different "window" areas than those after glass. Exterior could be kakishibu base mixed with pine soot (shouen 松煙) if the color is black. For reds, iron oxide (bengara 弁柄) can be used. Various tints and shades of browns can be created by mixing them together.
Kakishibu alone works very well for interior surfaces, and was often used that way for the nice brownish tone over time. On an exterior surface exposed to rain, it will tend to fade and you'll need to re-apply every year or two. If you let it age as it is, or kakishibu it once and then leave it, the sugi wood will tend to age to a nice grey when exposed to rain and sun. Of course it wont last quite as long this way.
Another technique used in certain areas was to lightly burn or singe the exterior wood. I don't know that this was done on window frames necessarily, but certainly on the plank siding.

Hope that's helpful.
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Re: Kominka

Post by Zasso Nouka » Wed Aug 24, 2016 6:07 am

Thanks for the explanation Brett,

Concrete maybe a quick solution for some people but it is hardly aesthetically pleasing and rarely blends into a natural setting and in addition sounds like it brings it's own set of problems anyway.

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Re: Kominka

Post by xxxxtom » Wed Aug 24, 2016 6:08 pm

Brett,
thanks for the info.Ill give it a go, I've got a couple of litres of kakishibu and a lot of old thirsty looking woodwork in many shades of colour from greys to dark browns.
Is the soot and iron oxide sourced from a specialist or a good home centre?
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Re: Kominka

Post by BrettRas » Wed Aug 24, 2016 8:42 pm

I ordered them online, finding them at a home center might be tricky these days. I'd guess you'd have more luck with the iron oxide as it's used for many other things as well. You'll certainly find a variety of synthetic colorants at the homecenter, just not sure they'll have the real thing.
One thing about the pine soot if you choose to use that, it dissolves much better in alcohol so I always use that to dissolve it before adding the kakishibu.
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Re: Kominka

Post by BrettRas » Fri Sep 16, 2016 2:50 pm

Update on the earth floor.

Hauled the concrete to the disposal site last week. Loosened up the underlying earth and removed big rocks and such. Leveled the loose earth across the entire entry as there were higher and lower spots before.

Now waiting for nigari (byproduct of sea salt making) to arrive from the next island over. Will then mix nigari and slaked lime into loosened earth and proceed to pack it all down as smooth as possible. Hope to have it done in the next week or two.


Here you can see some of the unevenness.
IMG_2572.jpg
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Leveling in progress.
IMG_2583.jpg
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Leveling finished.
IMG_2584.jpg
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Re: Kominka

Post by BrettRas » Fri Sep 16, 2016 2:54 pm

Also cleaned and rigged up an old anchor as a jizai kagi (pot hook). Anchor was one of several in the second floor storage space of Yukuzasama.
IMG_2537.jpg
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Re: Kominka

Post by Zasso Nouka » Sat Sep 17, 2016 6:29 am

Looks great Brett,

The packed earth is a vast improvement over the old concrete, blends in so well with the rest of your house. What properties do the slaked lime and nigari add to the earth ?