Energy saving: treat the walls against moisture!

[Christophe]

We are in the midst of "big jobs" to optimize the thermal buffer (photos will arrive) ... hence my relative absence of forums the last days...

First good surprise: a simple anti-humidity treatment of a wall entered in a room of the cellar made it possible to gain 5 ° C in the latter (while the outside temperature has dropped in recent days). And this BEFORE installing the insulation plates.

So I advise more than vigorously to all readers of this subject having a cellar with buried walls to deal with a hydraulic mortar or equivalent in order to avoid having to heat up the infiltrations ...

For the technical choice: the least expensive and effective solution is to use an additive in the mortar: SikaLite (€ 5 per kg) at 4% (instead of 2%) it works with the fire of God! The mortar is like "plasticized" ... Do not ask me the composition of SikaLite it must not be very "green" but in any case there are no particular precautions for its handling (it is a powder).

Voila ... soon more ...

[the middle]

We are in the midst of "big jobs" to optimize the thermal buffer (photos will arrive) ... hence my relative absence of forums the last days...

First good surprise: a simple anti-humidity treatment of an entered wall of the cellar made it possible to gain 5 ° C in this last one (whereas the outside T ° made a fall these last days). And this BEFORE installing the insulation plates.

So I advise more than vigorously to all readers of this subject having a cellar with buried walls to deal with a hydraulic mortar or equivalent in order to avoid having to heat up the infiltrations ...

For the technical choice: the least expensive and effective solution is to use an additive in the mortar: SikaLite (€ 5 per kg) at 4% (instead of 2%) it works with the fire of God! The mortar is like "plasticized" ... Do not ask me the composition of SikaLite it must not be very "green" but in any case there are no particular precautions for its handling (it is a powder).

Voila ... soon more ...

Hello,
This info interests me; I explain
My exterior walls are built with everything, and they are in terrible shape. The house is over 100 years old.
In addition, there is almost no color on these walls, which are sometimes cemented, sometimes, porous bricks; sometimes stones ...
As soon as it rains, I see these walls absorbing water ...
So, I said to myself, wet walls, that makes me a lot of calories lost.
So, I think maybe a good water repellent color would be a good start to insulation ...
No?

[Christophe]

Are you talking about a water-repellent color from the outside or inside? Do you have interior insulation?

I think that a facade paint (of the pliolite type for example) would not be sufficient. It is just made to "hold" to humidity not to make a real anti humidity barrier ... a treatment with a hydraulic mortar would be necessary whether it is from the inside or the outside.

It is to be studied on a case by case basis, but I think that in your case, a complete treatment by the outside would be more interesting (lifespan of the walls) ... finally it would be quite inexpensive with SikaLite: 1kg to 5 € is provided to make 50 kg of water repellent cement. Mixed with 2 kg of sand for 1 kg of cement, you get 150 kg of hydraulic mortar for a very low cost ... compared to other treatments ...

Now I'm not a pro at treating humidity ...

[Christophe]

If your house is not insulated from the inside, you might as well kill two birds with one stone: insulate using the hydraulic mortar technique!

This will not only deal with humidity issues but also insulation.

More info on this document: https://www.econologie.com/guide-fiche-t ... -3509.html
and in this new downloads section:
https://www.econologie.com/habitation-is ... -3482.html

[the middle]

Are you talking about a water-repellent color from the outside or inside? Do you have interior insulation?

I think that a facade paint (of the pliolite type for example) would not be sufficient. It is just made to "hold" to humidity not to make a real anti humidity barrier ... a treatment with a hydraulic mortar would be necessary whether it is from the inside or the outside.

It is to be studied on a case by case basis, but I think that in your case, a complete treatment by the outside would be more interesting (lifespan of the walls) ... finally it would be quite inexpensive with SikaLite: 1kg to 5 € is provided to make 50 kg of water repellent cement. Mixed with 2 kg of sand for 1 kg of cement, you get 150 kg of hydraulic mortar for a very low cost ... compared to other treatments ...

Now I'm not a pro at treating humidity ...

Yes, you're right...
But I'm not good at putting cement (exterior wall)
That's why I was talking about painting ...
Thank you for your answer which seems to me full of truth ..

[Christophe]

Not talented? Pfff ...we are all gifted but it is the others who want to make you believe that they are more so than you ...

I made my first hydraulic mortar of my life 3 days ago ... and apparently I did well ... Applying a mortar is not really harder than a paint (and personally I prefer even)!

But I haven't done a complete house, it's true, but now I'm sure that by following the "instructions" and finding advice (for example in the Leroy M. guide: https://www.econologie.com/construire-et ... -3482.html ) there is no reason not to get there.

After a few months of "small" work at home, I noticed one thing: home renovation is a very simple series of steps, you just have to choose the right products for the situation and that's the most delicate stage... (and often the pros do not necessarily give the best solutions but the most profitable for them ...) ... but fortunately there is this forum

Then for the application of the product, it is enough not to make "big" errors ... and in 99% of the cases it works

[I Citro]

I did not understand if your "SIKALITE" was or not a waterproofing?

It seems to me that we must ban waterproofers for non-buried walls because they prevent the construction from breathing which can generate humidity and mold inside the house forcing the installation of a very effective to fight against the thermos effect that we will have generated ...

For my walled concrete cellar, the SIKA products that I was offered seemed VERY EXPENSIVE ... but they have a reputation for recognized efficiency ...

For the exterior walls, I treated mine with a water repellent spray ... it prevents the walls from soaking up moisture without preventing them from breathing.

[the middle]

:?: I did not understand if your "SIKALITE" was or not a waterproofing?

It seems to me that we must ban waterproofers for non-buried walls because they prevent the construction from breathing which can generate humidity and mold inside the house forcing the installation of a very effective to fight against the thermos effect that we will have generated ...

For my walled concrete cellar, the SIKA products that I was offered seemed VERY EXPENSIVE ... but they have a reputation for recognized efficiency ...

For the exterior walls, I treated mine with a water repellent spray ... it prevents the walls from soaking up moisture without preventing them from breathing.

Yes, I have been told for a long time, you have to let the walls breathe ...
I find this normal.
More ...
For me, if rainwater gets too easily into the walls, it becomes a huge thermal bridge.
I have the impression that we left for a famous debate ...

[Christophe]

:?: I did not understand if your "SIKALITE" was or not a waterproofing?

It is ... since it "transforms" a classic mortar into a hydraulic mortar ....
Here is his doc: http://www.sika.fr/construction/document/nt/nt202.pdf

It seems to me that we must ban waterproofers for non-buried walls because they prevent the construction from breathing which can generate humidity and mold inside the house forcing the installation of a very effective to fight against the thermos effect that we will have generated ...

In direct plaster I agree it must not be very good (but good in comparison with walls completely soaked in exterior moisture ... it may be no worse ...) but it is however good hydraulic mortar which is used on page 4 of this doc: https://www.econologie.com/guide-fiche-t ... -3509.html

On the other hand, it is put on top of the insulation, this one must therefore be well chosen to allow the house to "breathe" ... In all cases an air space can be added with a small cladding .. .

For my walled concrete cellar, the SIKA products that I was offered seemed VERY EXPENSIVE ... but they have a reputation for recognized efficiency ...

See my remark above: the pros do not necessarily offer the most economical solutions ...

I think we offered you two components which are very expensive (and "oversized" to treat a cellar since they withstand very high pressures, it is this type of cement that is used to waterproof electrical dams. ...) but SikaLite seems to have an excellent efficiency / price ratio ... 5 € for 150kg of mortar is enough to make a few m²

For the exterior walls, I treated mine with a water repellent spray ... it prevents the walls from soaking up moisture without preventing them from breathing.

Is it a mineralizer? If yes, I also studied this solution but it was quite expensive (20 € HT per L for 3 to 4 m²). But a mineralizer prevents the wall from breathing since it creates a layer of synthetic glass, it's probably not what you used ...

[Christophe]

it becomes a huge thermal bridge.

Uh it's more really a thermal bridge, it's much worse it's a bit like if you had a rainwater tank in your living room that you constantly heated ...

If you can (= if you want and you have the "right") do a test on a small room with Sikalite and a small cladding ...

How much energy does your house consume and for what surface?

I have the impression that we left for a famous debate ...

Cool! That way everyone will learn things