An octagonal passive house in straw bales

[bpval]

Hello

http://www.octonome.com/

(was missing www)

Hello

[jean63]

Hello

http://www.octonome.com/

(was missing www)

Hello

it is good without www, it is accessed from the johnix site. There must have been a pb during the connection.

[sam17]

it is because of. who is at the end of the address that it was wrong.

[johnix]

johnix =>
I understand why octagonal framing is not too expensive; the specialist does this in series ....... there are only dimensions that change..bravo for his idea.

In fact, it is true for the plans and the design, but not for the realization: we bought the raw sawn timber, and it was cut to length and assembled on site.

There may also be less and less boots replaced by faster rollers to transport to storage locations?

I have often heard this remark; but most farmers keep an old baler on hand, because there is always demand: people who have horses, rabbits ... and not necessarily manitou to lug the big boots.

It would take a specialist for the roofing with pre-cut tiles to fit the junction of each triangle. It must be celled with cement mortar all these "ridge" tiles (which are not really).

We can not pre-cut the tiles, because each one has a different length.

The arches were not sealed with mortar, only the tip was. On the other hand, the roofer placed a ventilated enclosure and nailed the cut tiles.

I'll see it well, covered with shingles in red cedar.

It is not in the constructive habits of the corner. We preferred to avoid choices that could have complicated the obtaining of the building permit.

I spent time on your site and I see that you opted for a sophisticated VMC German not sold in France (bravo Borloo ...) and therefore not subsidizable:

Meanwhile, we have changed our minds: we will take a simple VMC 2F, not subsidizable, but less expensive. For domestic hot water, we will probably take a thermosiphon + an ordinary balloon.

Viessman stops production of Vitotres this month.

Is the exterior coating done? Can straw bales stay exposed to rain without coating during installation without the risk of absorbing moisture?

The coating is done (it lacks the last layer on the outside). Otherwise, the straw could rot fairly quickly.

If you keep your budget 150 000 euros is good.

We have good hope.

[jean63]

See the green house at 440 euros ..... and it is not passive but active; with 000 euros more it's expensive for a so-called green house =>

https://www.econologie.com/forums/post64109.html#64109

[jean63]

johnix wrote:

In fact, it is true for the plans and the design, but not for the realization: we bought the raw sawn timber, and it was cut to length and assembled on site.

I guess it's octonome that made the cuts and assemblies. This is not the first comer who can have fun building such a frame and framework. And then you need a hoist (crane or other), scaffolding .....

I would like to have details on the dimensions of the elements, spacing ... etc.

=> I saw on the site that everything is built around a central post which seems to be a tree trunk.
The wood (douglas) was not dry because cut recently, is not it a disadvantage for the straw (contact between the poles and the straw) + deformation of the wood when it does not dry well flat and forced?

In my MOB, the frame is douglas, but for safety it has been autoclaved vacuum pressure): attention to termites that go back to the north with global warming!

It's just that I really like everything that is wood and I do not understand how we insert the straw boots in the walls between the wooden posts and also how lime is adhered to the straw and the wooden poles (straw boots that must be perfectly aligned and do not buckle !! a straw boot is not a brick or a block).

=> For the installation of the boots, I have the answer, I went to see on the site, what would worry me the most is the humidity in the straw .......

On the inside, is there a plasterboard or other board against the straw or a lime plaster directly on the straw?

Are the elements nailed or screwed together, or with ankles (old carpenters technique)?

=> I saw on the site (metal fixing plates) ..... but how is the central post fixed to the ground? what makes the house stand, its octagonal shape?

In my MOB, panels made of CTBX poles and plywood panels (exterior quality: in case of rain during construction) and which constitute walls and roof, contribute to the bracing, that is to say they prevent inclination of the structure in the event of a storm (for example).
The house suffered the storm of 1999 (winds over 150 km / h), there were some crunches but it resisted well. On the other hand, I see that in the USA the MOB do not resist hurricanes, but we are not there yet!

[jonule]

yes it is on it is not obvious an octagonal house, and have to ask for some extra, whether hollow block or straw bale ...

if not to put the straw boot you have several technqiues, either in a formwork wood, or nebrasca method (filling small wood without structure, but no floor).
I also saw between wooden poles, sandwiches between wooden slats + straps between boots ...

on the other hand why do you say Jean63 that wood poles must be perfectly vertical and not curl?

otherwise, the boots can be cut very well with the saw with wood, one can work on plan or not ;-)

[jean63]

jonule wrote:

yes it is on it is not obvious an octagonal house, and have to ask for some extra, whether hollow block or straw bale ...

and yet, they came to make a passive house for 150 000 euros with large living room + 3 rooms + garage ... while the passive house of Belgians-Ardennais cost 310 000 euros (although very rectangular) with another technique more expensive insulation I think. It is 2 times more expensive, but maybe a little bigger !!
https://www.econologie.com/forums/une-maison ... t3520.html
http://passive-aventure.vivao.be/spip.php?article87

Maximum use of healthy and ecological materials
The cost analysis of this construction must take into account the systematic choice of the most healthy and ecological materials possible:
Native wood (except Canadian wood cladding), untreated
Hemp wool instead of stone wool, Pavatex
Fermacell
Sterling OSB
Clay plastering, raw clay mass bricks
Oils and natural paints

jonule wrote :

if not to put the straw boot you have several technqiues, either in a formwork wood, or nebrasca method (filling small wood without structure, but no floor).
I also saw between wooden poles, sandwiches between wooden slats + straps between boots ...

OK, so several techniques ....... johnix will tell us which technique was used.

The wooden formwork, I do not understand, we can no longer coat the boots with lime since they enter a formwork? and for the problem of "breathing" it is not a problem?

on the other hand why do you say Jean63 that wood poles must be perfectly vertical and not curl?

No, poorly expressed: error in my sentence; I speak, of course, of straw bales: do they form a rectangular parallelepiped (spelling?) perfectIncluding on the length do not they tend to warp and bend themselves?

[jonule]

a small boot for construction makes 40x40cm on 1m long.
My supplier told me he could make me 30cm thick, I could even 25 but 30 it suits me!
to support them under the roof I will put them all 2 rafters: on the meter long so, 2 rafters of 7x5 about.
I ask myself to support them with a fence (which would be stenciled on the rafters) but I am not sure, I try to consider negligible events, I still until next summer - )

so that the rafters are straight, it is necessary to fix them by pulls funds on another chevron which is thus horizontal to him, aligned with the level via metal hangers (pieces of metal for me);
a chevron along the wall of the attic, another on the fault, a last on the top beam and we have a base fixed by metal leg to the supporting structure of the frame, it is enough to fix the rafters with the pull up and slip in the straw boots.
previously, the vapor barrier fabric is assembled against the existing small rafters under slate roofing.

here is my solution for insulation straw boots under roof renovation.

to return to our sheep, so it is either a formwork wood or an alternative! what I chose, for a lower cost.
the guy I know to fuck the fact with wood shuttering, I can go take pictures if that tells you!

[Chatham]

The wooden formwork, I do not understand, we can no longer coat the boots with lime since they enter a formwork? and for the problem of "breathing" it is not a problem?
No, poorly expressed: error in my sentence; I speak, of course, of straw bales: do they form a rectangular parallelepiped (spelling?) perfectIncluding on the length do not they tend to warp and bend themselves?

The wooden structure is necessary to take up the structural forces because the straw bales have no cohesion between them and cannot support the load (and must not, otherwise they would settle which would cause the plaster to burst and would decrease the insulation (it is the air of the "voids" which insulates).
The straw bales are not precise mechanical bricks, the length and thickness dimensions are approximate the width is more precise and their geometry is also approximate (depends on the settlement and the humidity rate)
Important thing to check: if the boots were made with straw well dry otherwise it will ferment ...
Alas too: very few farmers still use these old balers: practically everyone uses the rollers because it saves time handling ...