wall moisture problem that explodes you know why?

[Obamot]

Very interesting. I'm going to read that at rest.

[dedeleco]

Still to read especially on the crystallization pressure of salts that break the building materials, responding to eng -venir.fr:
http://infoscience.epfl.ch/record/11875 ... YH_8a1.pdf

[dedeleco]

And the following exciting 2 part:
http://infoscience.epfl.ch/record/11875 ... YH_8a2.pdf
from the very pro site
http://infoscience.epfl.ch/collection/I ... earch/ENAC

[dedeleco]

The crystallization pressure reaches thousands of atmospheres in closed wall pore, enough to break everything :
http://infoscience.epfl.ch/record/11875 ... YH_8a1.pdf



Basic scientific demonstration for eng-avenir.fr related to the difficulty of nucleation of the crystals !!!

[eng-avenir.fr]

Following all the professional answers, I asked my clients how they now talked about humidity.
First for them it was a scourge whose market is highly prized by big international shops that scam its customers and we make a negative idea.100% of my customers did not trust with the process of drain by depression, they thought it was a gadget, some a scam, today the result is very satisfactory all say that their first impression was false and that they are all satisfied with the SPI it is its name in Spain.
Those who had problems with the salts no longer have the walls repainted the paint no longer lifts clear I bathe in happiness of satisfaction, I send you photos.

When installing the SPI.

The SPI facade eliminates the moisture that is in the wall behind the tiling that served as a mask, and especially false orientation of the customer.
This photo is the same as the 1 but repaired wall and repeind 2 months later, which would not have been possible without the SPI.
Glad to share my joy with you, without asking anything in exchange only my thesis is confirmed and I pride myself on the advantages of the devices.
Thank you all of you are immersed in research, congratulations to you all, the job resume with many salons, fairs etc ...
I continue to promote this market on Spain and I search on France one who would like to take my follow because it is difficult for me to cut in two.
I wish I could give my knowledge so that the young people can take over.
Kind regards, I continue to follow this debate which is very holy, because you are at the height of your skills!

[Obamot]

It's normal that things are better in Spain, there is no more water in your home!
(ok, I'm leaving and won't come back today)

All kidding aside, a sketch to illustrate this kind of drain and how it works would help us "understand" ...

[dedeleco]

My "understanding" is that it works for repeated evaporative and condensing humidities coming from the ground through the wall, but without liquid water flowing by direct flooding, due to poor drainage or an overflowing river or the water table that goes too high.
By aerating and sucking through holes (and also by electromigration), this wet steam rising slowly in the wall, it avoids re-condensation and evaporation with destructive salt deposits, at least over the holes, which dry the wall.
Below the holes, the salts dissolved in the liquid water that get evaporated at a certain level below the suction and drying holes, will continue to be deposited faster, given the faster evaporation, and if it is in the foundations of the wall, the strength of these salts, deposited little by little in the foundations of the wall, can be catastrophic after a certain number of years of accumulation, cracking the walls, like the 2003 drought !!
So instead of having this on the surface of the wall, as in the photos, we risk having it with a great delay, in the foundations, in the place where the water with salts evaporates, lower.
In my opinion, it would be good to ventilate and dry the neighborhood of the foundations so that the salts are deposited only outside the walls and their foundations.

If there is flooding by the arrival of liquid water by gravity, this system will not avoid anything, but will dry up faster, after end of the flood.

Finally this technical post was put to make known in France this Spanish process and to find distributors.
It's a bit of camouflaged SPAM.

In many cases, boring aeration holes, outward, are enough to dry a wall, poorly ventilated. Even changing the plaster for a porous plaster can suffice ..

[chatelot16]

a big flood is a good way to solve the moisture problem: it dilutes all the soluble salt, and then it dries faster

this is the problem of salpetre

salpetre was produced at the time when the building was used as a stable: the manure fed the bacteria that produce salpetre

the special solubility characteristics of the salpetre make it stand out from the wall long after

to avoid having a salt problem, evacuate a maximum of soil on the floor of the room to be arranged, rinse the walls with large water

of course when a piece has been built without care where there is salpetre it will not end to emerge ...

[dedeleco]

The problem is not that the saltpeter, but especially calcite a little soluble (but slowly as in the caves function CO2) which migrates, which does not leave quickly with a large flood of short duration, and which further damages the foundations, poorly made, after drying.
A good ventilation of the foundations by classical drainage is useful because the water leaves by evaporation instead of going into the wall to recondence higher in the wall colder than the ground in winter !!
In addition, calcite is deposited in the drainage.