Renovating vaulted cellar - experiences

To renovate our damp basement, we excavated around it piece by piece down to the foundation walls and insulated it from the outside. Now it is completely dry. Yes, it was quite an effort – but in return, we should have peace for the coming decades.

I spoke with a few companies today. Some said that vaulted cellars are difficult to impossible to make completely airtight.

And that's exactly how it is. To me, the pictures look like a completely normal vaulted cellar. It is damp because it is simply not sealed and has direct contact with the earth. The floor was often just rammed earth, with you there are just some stones on top, which makes no difference for the moisture. It is well suited for potatoes, vegetables, wine, etc. A refrigerator also doesn't mind that. But as a living space or even as storage for anything that can mold, it is simply unsuitable. Nothing rises up into the rooms above either, that is just completely normal. Didn't you inform yourselves a bit before buying?

We have had a refrigerator, stove, washing machine, dryer, decorations, supplies, tools, and even some building materials in such a cellar for 3.5 years. Nothing has molded anywhere yet. The cardboard just gets a bit damp after a long time. But really only a little. I would have expected even more problems.

What kind of cellar do you have and what exactly have you done?

We have had a refrigerator, stove, washing machine, dryer, decorations, supplies, tools, and partly even building materials in such a basement for 3.5 years. Nothing has molded anywhere yet. Cardboard just gets a bit damp after a long time. But really only a little. I would have even expected more problems.

But your basement has much less earth contact. If cardboard gets damp, it can eventually mold. I also wouldn't store anything important / expensive there.

We have been through pretty much everything with our basement as well. You can’t access all sides because, for example, there is a neighbor’s storage hall at the back – you can’t dig underneath it. We sealed part of it from the outside and applied restoration plaster to another part. Then the ventilation system was added. The sealed walls are fine. The restoration plaster on our basement was already damaged after three years, with mold and everything. Removing something like that in a basement without windows is a complete disaster.

But your basement has much less earth contact.
If cardboard gets damp, it can eventually mold.
I also wouldn’t store anything there that is important/valuable to me.

Yes, maybe after 10 years. Damp might not even be the right word. After 3 winters everything is still fine. And due to lack of space, we store most things in exactly the room that is deepest in the ground and has the smallest window.

If renovation plaster is saturated after 3 years, the wall was obviously very wet and then it did exactly what it was supposed to do.