Moisture in the exterior wall of a 300-year-old house

There are many methods to dry such masonry and consequently also the floor. Horizontal and vertical sealing methods, injections, drainage .. Such things should be assessed by a specialist. You quickly spend 50000-100000 on something like that.

I just think to myself:

If I now get large infrared heaters to remove the moisture from the walls, I might not have found the cause yet.

Or how do I find out whether it is rising damp (since it is located in a flood area with very high flood levels) through the floor slab or from the 2003 flood.

Is there any way to find this out?

The measurement on the floor (tile floor) showed a value of about 70.

What do you say about that?

As said, not so trivial. Order a specialist. Messing around yourself certainly does not solve the problem.

Again: This house is built without cement. There was no Portland cement 300 years ago. Please get an architect or a good master mason with a love for the profession, and consult on site. K.

We will bring an expert on site.

But what I have been able to read online now is basically the following: With such (old/thick) rubble masonry walls, there aren’t many capillary parts that draw moisture up from the ground. That’s why a horizontal barrier, regardless of the type, is not necessarily an effective solution or mostly no solution at all.

But that also means that it might only be damp on the surface. So it could be that in the long term we will have to set up a kind of perimeter heating to simply get the moisture out.

Of course, beforehand new renovation plaster will be applied and even before that, the whole thing will basically be dried out with infrared heaters.

([We have no musty smell or even mold in the house at the moment. It’s just the above-mentioned device that has indicated the moisture and the plaster is loose there])

Hello, very interesting topic. Our masonry is similar. Do you already know what it could be due to?