Rising moisture problem crawlspace design

[Obamot]

... Boudioux, you are not yet going to relaunch this debate, which is closed! Do you still believe in the advice of Dr Jekyll & Mr Aerial you? ^^ We should not believe that this is what will "clean up your walls" and stop playing sorcerer's apprentice? ^^ In addition, you are just doing that prevent natural soil moisture - relatively high here due to a body of water in the immediate vicinity - from escaping. The degree of hygrometry will therefore rise against the walls => it is just the opposite that should be done.

The other solution has already been mentioned, it would be to put a cement mortar with possibly a little lime (the cement does not prevent moisture from coming out when necessary). We must take the trouble to read what we have already written. No need to relaunch this debate eh ... WE DID IT!

Can't wait to start digging ...

[moby25]

I do not want to reopen the debate, I said that I would take the test, so I give a feedback of this experience that's all.

[Obamot]

The best would be to dig in silence ^^

[aerialcastor]

Do you still believe in the advice of Dr Jekyll & Mr Aerial you?

You are not too embarrassed. You cheerfully criticize my advice, to take it back to you the next sentence.

We shouldn't believe that this is what will "clean up your walls" and stop playing sorcerer's apprentices? ^^ In addition, you are only preventing the natural humidity of the ground - relatively strong in this place because from a body of water in the immediate vicinity - to escape. The degree of hygrometry will therefore rise against the walls => it is just the opposite that should be done.

This is what I said among other things here

I am more than skeptical about the tarpaulin technique.

The problem is not the humidity level of the crawl space, but the rising humidity by the breeze blocks.

By putting a tarp you will block the evaporation of water. Suddenly the ground of the crawl space under the cover will be more humid and therefore the ascents by the breeze block will be more important.

This is typically what we observe in old houses (so without capillary cut like at home), when we replace the clay or lime tiles (which lets water vapor pass) by concrete tiles ( blocking water vapor).

With physical explanation here

Water comes out from where it can because physics wants pressures to balance.
This is the equilibrium of the partial vapor pressures.

With other references here


Yet here you had widely criticized:

After all this time we have come to certain conclusions, while Aerialcastor continues: to push open doors, to "copy / paste" on the internet without substantive discernment, or to try to redo debates that have already taken place for problems which have already found their solution (or at least the modus operandi to achieve it) .. It is a typical attitude that someone has "when trying to learn" ... (which would be entirely up to him). honor) but not when trying to make a diagnosis ...
...
Do not see any personal attack, but Aerialcastor should agree that in view of the above, those who pass by there would be well advised not to give too much credit to what he says

But hey you have to "try to learn", so it is normal that there is not a trace of excuse ....

[Obamot]

Stop your chariot. Before you set fire to Dede, since I told you to drop ballast and now that I also make comments to you, it's my turn. Who will it be tomorrow?

No you don't just say hiccups - and in this case you made some sensible comments => that's what I meant when I spoke of breaking open doors - but other times you often understand what you okay .... Yes it is absolutely necessary to be wary of those who lack rigor and mix the brushes, sorry if I do not comment on your words, period!

You see Moby, you shouldn't have posted because I feel that your thread will still slide ... ^^

[moby25]

Yes, this subject will still be the subject of much ink

This experience can still tell if there is a layer of water-repellent cement before the last row of concrete blocks.

[Obamot]

I was also saying, big barrel, so you did it on purpose. the best is to leave this thread permanently. Bye.

[dedeleco]

Good start simple moby !!
Plastic film is a simple solution that works since everywhere it is put under the tiles without having much more moisture in the concrete walls even without water repellency.
It can be removed easily.
Apply the film well on the floor.
An optimal possibility is to vent outside with a fan under the film along the ripples that we see today.
Currently there must be condensed water vapor underneath this film ???? at least the cold nights and days outside.

To dig, be very careful with do not destabilize the walls who seem to see the photos almost without deep foundations for some of the bizarre support of the beams.
So dig very little with great care !!.

Draining very well will not remove the evaporated water vapor from the soil, as I explained, in winter with hot soil the summer heat !!

If company, take structure damage insurance !!

[dedeleco]

aerialcastor refuses to calculate the speed of this process :

Water comes out from where it can because physics wants pressures to balance.
This is the equilibrium of the partial vapor pressures.

as I invited him to see this diffusion, that it is negligible compared to the slightest draft of air at less than 0,01m / s !!
https://www.econologie.com/forums/post194647.html#194647

aerialcastor never calculates anything, citing absurd and fuzzy links.

Raz the misleading aerialcastor bowl people like moby !!

[aerialcastor]

We are progressing on several points.


You already recognize that the partial vapor pressures balance each other, while there is not so long time you said that:

Afterwards, aerialcastor threads errors like pearls mixing all liquid water and steam water !!

Water comes out from where it can because physics wants pressures to balance.
This is the equilibrium of the partial vapor pressures.

true for liquid water with Archimedes, clearly visible in floods like Xynthia which drowns houses.
But this is not true for the water vapor entrained by the air of which it is a small proportion between 0 ° C and 20 ° C because what matters is the pressure of the air which carries its vapor with it in the wind. !!

Then you finally admit that you have to ventilate. Well here I do not put a link because on dozens of pages you said the opposite ...

as I invited him to see this diffusion, that it is negligible compared to the slightest draft of air at less than 0,01m / s !!

Here I am not too sure to understand what you mean.
If you talk about the water vapor which is contained in the air of the crawl space, the homogenization will go very quickly even if it will not be perfect, there will always be concentrated areas than others.
Hence the importance of having regularly distributed grids

Why it goes fast, because air still in reality does not exist, there are always temperature differences which create convection movements, and there in addition the crawl space has openings, which will create turbulence and accelerate the balance.
Everyone can observe this phenomenon when taking a shower: even with a very large bathroom, when taking a shower you can observe condensation on the mirror.

And I already explained to you why it cannot be calculated by hand:

Then make calculations on this kind of thing it's just a joke already you would have to know all the parameters, we know none (non-exhaustive list):
- relative humidity of VS and outside
- ventilation rate as a function of wind
- indoor and outdoor temperature
- contact angle of the capillaries
- absorption surface
- pore size of concrete blocks and plaster
- density of concrete blocks
- exact composition of the jointing mortar

But as you seem to say that it is calculable, go ahead please but the dots on the "i" and post your calculation to us.
There at least the discussion will be closed.