Tiny house build in Hokkaido

Dont forget the use of a water filed tube to level things!

John C Daley wrote:Dont forget the use of a water filed tube to level things!

Thanks John!

There’s the setup...🤙🏽

Peter

Nice, its a bit fancier than I have seen.
Some have a 1M rule attached at each end.

John C Daley wrote:Nice, its a bit fancier than I have seen.
Some have a 1M rule attached at each end.

Super high tech...🤓
Have it attached to this fancy seamstress tape measure when we are measuring from grade.

Otherwise just putting the can somewhere level and then filling it till the water line match’s the high of a confirmed/fixed point (Point A). Then just run that line to every other point (Point B, Point C etc.) we want to compare and adjust the location/height of those points to match Point A.

Not a pro by any means, but starting to get the hang of it and with a few meters of scrap tubing, a 6 minute weld job and some well water, you’ve got yourself a tool that never lies and never runs out of batteries. Do have to watch out for air bubbles though.

Pour tomorrow. Everything is ready I think.

Had a bit of down time so decided to take a 5 minute drive and do a bit of rock shopping at the beach. Not much of Japan is made with brick so finding sufficient quantities of used brick for our mass and core skin on the RMH would be difficult. Think we’re gonna have to go rock motif on this one. Found a fair few good ones and should be able to find enough to do everything without a problem. Beach rocks come come sand polished and the river is overgrown with plants right now so too hard to get to anyway.

No measurements, no architectural drawings or schematic plans. Just the two of us trying to keep somethings straight.

Looking forward to when we can brake the rules and not have to stay so straight...

Happy days...✌️🌞✌️

Here’s a look at a few of our test block rice hull biocrete samples.

Again, most likely no need for us to have absolutely solid blocks in any part of our construction plan. Just kind of wanted to get a better feel for mixing and an idea of what consistencies “hold together” and what “crumbles”.

Exhibit A- rice hulls and Portland Blast Furnace Slag Cement Type B (what I had laying around)

Exhibit B- rice hulls, homemade slaked lime, natural dry sifted clay from soil (earthen wear grade)

Exhibit C- rice hulls and a lot more clay ( burnt just for fun)

Exhibit D- rice hulls and castable refractory cement

All solid except for B, but B should still be good for a thick sub flooring insulation layer.

Followed the recipe John sent and pre soaked the rice hulls in all the mixes except in C. When I soaked the rice hulls I noticed a few creatures swim to the surface. One is the rice worm the other is the rice weevil. Think the way to Eradicate this issue would be to pre-boil the rice holes in borax water then try before dry filling cavities and earthbags. Lime would also make the rice hulls less palatable for any insects dine on.

Still up in the air on which mix design to use in which application, but I’m pretty sure we will do some form of processing no matter what the scenario.

There you have it.

Feel free to ask questions or make comments.

Thanks Peter & Co...🧱🤓🧱

Those bugs etc are interesting. Apparently we can eat them they are not harmful to humans.
WORLD WIDE WEB OF SCIENCE

Has research papers do do with rice husks, mainly burning etc
I will look for other data about the bugs
dealing with bugs in rice

Theres more!!!
6 benefits of rice husks

John C Daley wrote:Those bugs etc are interesting. Apparently we can eat them they are not harmful to humans.
WORLD WIDE WEB OF SCIENCE

Has research papers do do with rice husks, mainly burning etc
I will look for other data about the bugs

Nice to know that we can eat them. Even better if we can cook up a plan to keep them from eating our house. Read somewhere that boiling kills them and their eggs. Freezing too.

There’s one petrified in our test block. Looks kinda cool.

Peter

We have a foundation. Just in time. The weather gave us a window to pour and Mr Yoshida and our other neighbor Mr Shimizu came and banged it out with us yesterday afternoon. It started raining heavy again in the middle of the night, but everything seems to be set and the water will just help to slow down and give us a proper cure.

We have a family emergency that happened yesterday afternoon that’s gonna take us away from the project for a week or so. Not the best of timing, but still plan to continue the build when we get back.

So lucky to have the people around us. We live in a new place so far from everything we know, but feel so blessed to have this opportunity and the support of the local community.

Will keep you posted as the journey continues.

Peter, Mimi and Chimichanga...

Do the stirrups have posts into the concrete?

John, they do. See the earlier photo...looks a lot like trade name Bowmac that we use in NZ. They hold up our carport and will soon hold up a back veranda for an outdoor kitchen.

John C Daley wrote:Do the stirrups have posts into the concrete?

Yeah! Mr. Yoshida welded them up for us. Says they will help to keep the roof from blowing off if we get heavy winds.

😉

He is on the money!
Do you get high winds where you are?

So what happens next?

Just been reading your posts about the floor again.
I wonder if a vapour barrier, in the form of concreters black plastic should be used under the floor?

I have been thinking about underfloor insulation.
I am aware in some ares where the weather is not extreme, insulation is not needed,
And I found this ;
In areas with milder temperatures and higher ground temperatures, under-slab insulation is often not required, and not insulating the slab will often result in more stable indoor temperatures.
Underfloor insulation


Corner insert of this documents talks about when insulation may not be needed.

hey  this is cool =) good work. i love a good photo documenting =)

as for some of the things you are asking, my two cents is to to build the floor you are visioning, and then later after the basics are in, or if it doesnt work as intended, build another floor on top.
potentially thick sand with tile set on top, in this way you could consider adding a hot water loop under the floor for some gentle heating of the floor. but all this on top of your earth floor, or in a pinch -a good rug.

but anywho your plan for the floor sounds good, adding in a lot more sand and gravel if you can score it.

seems like you are working out some good recipes, and just to throw out one potential idea is you might look into a way to do movable forms. i guess a bit like LSC in that it's a slipform, but more along the lines of making the bricks in place. and inch by inch building upward, where you keep moving the forms . do as few or dozen in a day, wait for mostly dry ish, and keep on keeping on. i have seen some neat examples of this...i will see if i can round you up some links.

when i did some building with hempcrete, which yeah is very similar to what you are doing, we were doing bricks with a mortar matrix, which is good way to go.

well google isnt cooperative today, or i dont have the right keywords...but i did find one link i was thinking of --->

https://permies.com/t/49057/bricks-easy-adobe-home

from here...but yeah this is pretty sensible anyway, to form the bricks in place, and then keep moving the forms, a lot like slipstraw (LSC) or slipform stone.

you can make your forms so that there's a space between them for a layer of mortar in between each block, or do it with with sections of your bricks with no mortar in between (so infill, or load bearing with mortar). if you form them in place you can also make them really big.

and youve probably looked into soil crete of some kind, but a simple way to do soil crete on floors...is to get the dirt/subfloor or whatevers prepared....

once its prepared and level ish...throw around a lot of dry sand and cement right on the floor...then go through with a small tiller or other earth mixer gadget...doesnt need to be a jackhammer, but just a small tiller to mix up the dry ingredients you threw around with your local subsoil/subfloor materials. then moisten it as you go and tamp it down/smooth it at the end.

Thanks for all the info folks!
On the road right now, but will be sure to get back to you with my thoughts and findings in the very near future.

Cheers, Peter

Hey Pete;   Say hello to Willie Nelson while your on the road!
Hurry back and continue your build. We are all enjoying your thread!

1am and still driving. This happened just before sunset...🌈

Now that we’re driving in the car, Mimi has time to recap all the stuff that Mr. Yoshida said to her while they were pouring the foundation.

My favorite quote is:

“I’ve never constructed a shack, this well built, in my whole career” Mr. Yoshida 🚬

John C Daley wrote:He is on the money!
Do you get high winds where you are?

So what happens next?

Hey John,

It’s not that we get really high winds very often here, although the wind can pick up from time to time.

It’s really about the fact that the proposed house construction is so light and the western portion of the house has a pronounced overhang. Figured it was a good idea to get a solid connection to the earth.

As far as for what’s next, we are away, so it gives me a bit of time to step back and evaluate. The weather is staying overcast with intermittent showers for the next few days, so that should help give the foundation some time to slow cure.

I think the next step is to lay the outer course of block work and determine where the door is going to go. Think we will leave out the top two courses of blocks to accommodate the door. Then work out a space for a “mud room” just inside the door with ample room for the door to swing in and allow some space for wet shoes and boots. This area will be framed out so that we have a step up onto the finished plaster floor of the main living space.

After the block walls are in probably dig out excess clay soil from the area inside the perimeter of the foundation. Level that and put a layer of tamped level gravel in to use as a temporary working floor.

From there infill the space between the two course block wall with insulation. What to use here is still up in the air. Think rice hull and OPC mix similar to my sample posted earlier. Not sold on the idea of putting organic based dry fill rice hulls in plastic bags and putting them in between concrete block that sit just above grade. Afraid they’ll be subject to potential water damage and decomposition and we’ll never know it. I know that by adding a mix of some Portland based cement, we will lose a portion of the insulation value, but also  feel this mix is very unlikely to be prone to insect damage. Correct me if I’m wrong here.

Next will be the sill plate with some form of water/vapor barrier. From there the loadbearing timber frame that’s it on the outer course of  blocks.

Next will be the roof in my mind. Sooner we can get a roof up the sooner it will have space that we can work even when the weather isn’t cooperating.

Let me know if that logic makes sense and any thoughts or ideas regarding mix designs for rice hull insulation would be much appreciated.

Thanks as always Peter & Co✌️🌈✌️

Will you be running tie rods inside the wall at the rear to hold the roof down?

From reading widely I cannot find anything which shows that insects are a problem with husks. The silica content helps that.
Also water absorption is not an issue either.

There is evidence that the use of rice husk ash [RHA] will protect against insect damage,
Rice husk ash prevents insect attack
Based on this study, RHA may have potential for refinement into an effective protectant for use in management of stored grain insect pests

Knowledge bank for rice production and waste products


From
rice Hull house
The rice hull contains approximately 20% opaline silica in combination with a large amount of the phenyl propanoid structural
polymer called lignin. Such a high percentage of silica is very unusual within nature,4 and this intimate blend of silica and
lignin makes the rice hull not only resistant to water penetration and fungal
From
insulation use
Amount of rice husk required for insulation
Our cost for a trailer-load will be 18 tons x $15/ton = $270 plus $3,600 for freight, making a total cost of $3,870.
If, as Olivier says, a ton of hulls will insulate 222 cu ft of wall space, 18 tons will do just under 4,000 cu feet.
If we were to insulate the garage walls with hulls as well as the house, we would need about 2,400 cu ft for the walls and 2,800 for the ceilings or 5,400 altogether.

leila hamaya wrote:hey  this is cool =) good work. i love a good photo documenting =)

as for some of the things you are asking, my two cents is to to build the floor you are visioning, and then later after the basics are in, or if it doesnt work as intended, build another floor on top.
potentially thick sand with tile set on top, in this way you could consider adding a hot water loop under the floor for some gentle heating of the floor. but all this on top of your earth floor, or in a pinch -a good rug.

but anywho your plan for the floor sounds good, adding in a lot more sand and gravel if you can score it.

seems like you are working out some good recipes, and just to throw out one potential idea is you might look into a way to do movable forms. i guess a bit like LSC in that it's a slipform, but more along the lines of making the bricks in place. and inch by inch building upward, where you keep moving the forms . do as few or dozen in a day, wait for mostly dry ish, and keep on keeping on. i have seen some neat examples of this...i will see if i can round you up some links.

when i did some building with hempcrete, which yeah is very similar to what you are doing, we were doing bricks with a mortar matrix, which is good way to go.

Hey Leila,

Thanks for all the tips.

I was thinking the same thing about the floor. Will make a basic working floor with gravel while we’re building. Then fill in the layers once we get closer to finish. Have to calculate amounts and depths of layers to insure we don’t end up making it too thick and not have room to add if we need to in the future.

Based on our time schedule likely going to use a lath system as mentioned in previous posts to avoid long waits between drying times.

Interested in the brick build in place idea, may try that with a more clay rich cob rice hull mix on the inside. Make the lose fill lath cavity a bit thinner, say 30cm, then add 10cm of heavier plaster, cob in the style you mentioned. Somewhere between mass and insulation.

Will see as the build continues and we get closer to that portion.

Thanks again, Peter✌️

John C Daley wrote:Will you be running tie rods inside the wall at the rear to hold the roof down?

Will have a base frame tied down with anchor bolts, embedded in the top course of the stemwall.  

Hey John,

I feel relatively good regarding pests. Think the RHA (rice hull ash), lime, and borax can also help to insure an even better resistance to pests.

The one article you did send me regarding use of rice hulls to insulate between block walls, to help keep produce cool in Africa, suggested they had to put the rice hulls in sealed plastic bags or they would “quickly be infested by termites”. Not sure how accurate that is but...

I feel relatively good about working out an effective build insulation design for the lath wall infill portion of the project. It’s the floor and the insulation space between the
Blocks that I’m most hesitant about.

Just watched a YouTube video where a guy pulls up his earthen floor, which he first insulated with LSC (light straw clay) all of the straw had decomposed. He had used a vapor barrier etc etc so he’s not sure why etc etc. I’m sure there are veritable that are not being considered in his case and I do understand that rice hulls and straw are different.

Link to LSC floor: https://youtu.be/RbkGflkkTQM

In reality LSC and cob are basically the same thing, just with different ratios of added materials. LSC is just super heavy on the straw side of the spectrum. People have been making cob with straw since before Adam and Eve, and the old buildings have lasted for a long time. Feels like the success of the straw in cob has some relation to the amount of clay which is encapsulating it. As Gerry said, “mummified”

How do you determine the sweet spot of the recipe, so you get mummification and still maintain enough of the insulation characteristics of the rice hulls, to warrant their use?

Kinda just throwing that question out into the cosmos. Maybe I’m over analyzing it. Maybe it’s something to consider.

Anyone have any thought on this logic?

LSC - Light straw clay

I my experience straw will always collapse over time under a floor.
In fact I tried to find and example around the world where it has worked and cant find a single situation.
I looked for acorns, pebbles, anything that can create an air space and will not collapse, to no avail.
This page below has useful info

Earthen floors

4. Insulation
This is the layer that is most often left out, but it can dictate energy performance and comfort. If you live in a hot climate, skip the insulation, because a cool floor is beneficial.
But if you heat your building, you want to keep the heat inside. If you don’t have insulation below your floor, then you are, in effect, heating the endless thermal mass of the ground below.
I use R-10 insulation for a typical floor and bump up to R-15 if the floor will have radiant heating in it. You want that heat to follow the path of least resistance into your space,
not down into the ground. And you need that insulation to be non-biodegradable, otherwise it will compost under your floor and disappear over time,
leaving you with a cracked & heaving floor. This is one place where I’ll use rigid foam, since the reduction in energy over time quickly offsets the impact of the foam manufacture.
For a natural alternative, you can use a rigid insulating mineral, such as pumice or perlite.

Maybe think about some electronics you can install to monitor the building

Think my last post may have been a bit misleading. We are not planning on using LSC for floor insulation. That was the closest material, I could find, to rice hulls which had documented before and after data.

So basically, we want to avoid relaying on cellulose based materials to insulate an on grade slab style natural earthen floor.

Will keep that in mind as we work out our layering system for the floor portion of our build.

As for a monitoring system, that sounds like a fantastic idea and maybe something we can consider in the future. For now I’m just pushing pennies around to get this building up and insulated for the winter.

There is so much to do and as this is our first building I really have no idea just how long it will take. We will keep working on it until the weather gets cold. If at some point we see we are not going to finish on time we’ll switch gears and probably just use the rice hulls, in large grain bags to line the interior walls and attic space of our present space with a focus on the RMH room and push through the winter in that. Continue the build in the spring.

For now we just remain optimistic and plug on with the build, keeping plan B as a last resort option.

Thanks again for all the input.

Hope to be back building in the coming days.

Will keep you posted... Peter⛰🤙🏽⛰

Totally off-topic, but drawing some bags for my nieces in the downtown.

Hanging at a friends old beach house by the ocean. New appreciation for traditional construction. Inspecting everything and trying to learn as much as I can, from what I see.

So much to learn...🙏🏼

Wonder how cold it gets there with no or very little insulation in the walls? Perhaps just a summer beach house? Yours in comparison is going to be like a fortress worthy of the Great Canadian white north eh?

Always learning Peter. That's great! I bet when you go to bed you dream of rice hulls and rocket stoves. :)

I was asking the same thing. Told my friend he should look into natural insulation bla bla bla. He listened, cause he’s a good friend, but alas quite a one-sided conversation...

🤓

Hey folks!  Just a quick update.

Still back at the family house on the main island. Probably here a few more days. Itching to get back to the build, but doing my best to do what I can here. Did manage to bring my macbook pro back from the dead. Thing was super slow and was barely able to open the internet on it. Consulted with a friend and told him my issues. Tried everything from resetting the NVRAM, PRAM to rebooting the SMC, but with little effect. Battery just wouldn't charge. He suggested I just take the battery out of the computer completely. I did. Now it's working like it's brand new.

As a result, I've had a chance to layout a new stove build in Sketchup. Here's a quick look. Will start a new RMH tread for this soon, but thought I'd just give a quick look at where I'm at. Based on Matt's original design with a few modifications to the brick orientation. Haven't changed any of the dimensions.

Like I said will go into further detail later and I'm sure I will have lots of questions as well.

Hope everyone is good.

Keep you posted...

Peter

Hey Pete;  Looking good, your going to love Matt's stove design!
Don't forget, 3.5 hrs to stove chat!

thomas rubino wrote:Hey Pete;  Looking good, your going to love Matt's stove design!
Don't forget, 3.5 hrs to stove chat!

Thanks Thomas! Will definitely listen. Might have to be in the am here, but haven't missed one yet. And the best part is I have endless free wifi right now, so bingeing a bit...

:)

More fun kicks in the down time...✌️🖤✌️

Home at last! And ready to continue building our new tiny home. Funny when you’ve been away for a while and you come back, it’s smaller than you remember...🏡😊🏡

You've been dreaming big lately so no wonder it 'appears' small.  :)

Moving along, slowly but surely.

Got the form work off and infilled the areas around the foundation. Earth on the inside and crushed stone around the outside. Will tamp and level. Then put up the first line of blocks. After that add more gravel inside.

My question is how much is enough gravel? I’ve read that we should have 6”/15cm under an earthen floor. Is this accurate?

I’ll insulate on top of that and then mor gravel. Followed by the base layer for our earthen floor.

All of this will be well above grade by this point.

Any advice would be welcome.

Thanks in advance...

Peter & Co. ⛰🌈⛰

Peter Sedgwick wrote:My question is how much is enough gravel? I’ve read that we should have 6”/15cm under an earthen floor. Is this accurate?

.....and I have read that 4”–8” of drainage gravel was the recommended amount to use. Such a wide margin as to the soil type and climate I'm sure.