cinderblock wood bvb insulation

[TATAMI]

Hello,

What do you think of the performance in terms of thermal insulation of the BVB wooden blocks produced by Kalliste?

Is insulation with their 19 cm concrete block sufficient for living in central France at an altitude of 500m?

Where would it be better to take a 14cm concrete block with additional insulation?

Thank you

[bham]

Could you give us some internet links, figures like thermal resistance, the lambda of the concrete block in question?

[TATAMI]

Ok, I have this: http://www.kalliste-eco-foret.com/Files ... erie_2.pdf

[bham]

Good now I see it more clearly; your house is not insulated, the thermal resistance R of your wooden walls = thickness / lambda
so :
R = 0,19 / 0,12 = 1,58 and you should know that in terms of insulation standard RT 2005, the R of a wall insulated from the inside must be at least 2,35 if I remember well
To make it more meaningful, you have to compare your 19 cm thick block with a thickness of insulation having the same R; if I take a traditional (wool, polystyrene) or natural insulation for which the lambda is generally 0,04, I obtain the same thermal resistance R = 1,58 with only 6,3 cm.
So a 19cm concrete block insulates as much as 6cm of insulation,
a block of 14cm (R = 1,16) as much as 4,6 cm of insulation.
So your concrete block is not enough to ensure sufficient insulation, which is a shame since it is as beautiful on the outside as it is on the inside and it is a shame to hide it.
I therefore draw your attention to the fact that there are hollow wooden blocks that can be filled with insulation and that in terms of insulation you have to count on the insulation both against the cold and against the hot.
I strongly advise you to go and get info on this site http://www.ideesmaison.com/Construction ... lculs.html and also page 7 to calculate the composition of your walls.
You can also see the construction of a passive wooden house
http://www.ideesmaison.com/Maison-ecolo ... oggia.html
and possibly change the perspective for another wooden house ...

[Gregconstruct]

This is great bham!

Clear, sharp, precise ... What more?

[bham]

Thank you Greg, hoping not to have made mistakes or Bucheron will fall on me

[Gregconstruct]

Yes, let's wait and see ...
Otherwise, it will be a pleasure for you

[TATAMI]

Hi,

Here is what I found about these concrete blocks on another subject of this site "maison-en-bois-kit-madrier"

Shai'ullud wrote:

I can just give some advice:

-I understand that you are heading towards a solid wood construction and personally if I find these buildings interesting from an isolation point of view (unbeatable) I always wondered how they are aging: especially for problems of drying the wood

...

[bham]

Tatami I understand that it is difficult to form an opinion, especially when someone says something and someone else says the opposite.
So in this case, you have to find out who is closest to the truth; when Shai'ullud says "interesting constructions from an isolation point of view (unbeatable)", you will notice that he brings no details, no proof, it is just the expression of his personal conviction, which, you l 'admit, cannot serve as proof of what he says; and therefore, we can affirm what we want, without proof, it's worth it; I even know sellers of materials who will tell you that 4 cm of polystyrene in insulation is enough, well yes why not. If you want to eat all your heating budget it's a choice like any other, it's like those who today build new and have a heat pump installed before thinking about the fact that they SHOULD make a passive house in investing € 15000 in more insulation rather than in a heat pump which will generate annual operating costs.
What I am giving you are figures that you can easily check on the links I have given you or on others using a search engine. Wood is about 3 times less insulating than insulation sold as such, it's a fact, I can't help it and neither can you; so if you want a house with wood just wood and which is insulated, well make a log cabin 30/40 cm in diameter and there you will start to have something correct in insulation (except thermal bridges of course).

Here I put you on the track, it's up to you to do the job of sorting information now.
Well at worst, if you pay well, give me your specifications, I will take care of making the choice for you.

[TATAMI]

Hello,
I take note of your answer Bham. I agree that we have to rely on figures.

A quantified study wants to demonstrate that despite this too low R, in reality these concrete blocks have a good insulation performance.
This study says, for example, that "the RT2000 does not take into account the behavior and real performance of buildings with distributed insulation and thermal inertia." "that it turns out to be unsuitable for evaluating the performance of heavy walls".

If you have a moment the report is there: http://www.kalliste-eco-foret.com/Files ... surfer.pdf