Basement exterior walls: one side damp up to 10 cm high, other walls are okay

Hello everyone,

we are currently renovating our basement. The previous owner paneled the walls in the basement with wood. There is a carpet on the screed.

Now we have removed the carpet and discovered stains. The damp stains ran along the wall, so we removed the paneling as a first step.

What can be seen there: The masonry is visibly damp up to about 10 cm from the screed. Interestingly, this was not observed in other rooms of the basement.

The question now is: What could be the cause? Which specialist (specialization) can inspect and repair this? What should I pay attention to in order to get a fair price?

Hello , what kind of house is it (year built), what are the basement walls made of, is the damp wall located in the ground, has it ever been exposed on the outside (if located in the ground), is it sealed in any way, is there a drainage around the house? The reason for a damp wall can be varied. Maybe you can give us a few more details =).

Hello,

I am getting back to you with an interim update.

In the meantime, an expert has been to the house, as well as several construction companies. The expert pointed out that the exterior waterproofing is defective. Most likely, the sewage pipe that drains rainwater is also no longer tight, causing the soil to become more saturated during rainfall.

The absence of a drainage system also leads to rainwater seeping along the wall, which further exacerbates this condition.

The construction companies that visited offer:

- Excavation (approx. 6 linear meters at about 1.80m depth)
- Excavation of a trench up to the connection point so that the new rainwater pipe can properly discharge the water
- Replacement of the old concrete pipe that drains the rainwater
- Replacement of the old waterproofing including plaster (so it will be completely removed and redone)
- Optional: Installation of a drainage system

Costs range between €5,000 and €8,000.

That sounds like "moderate horror." Have the drainage done at the same time.

Or do it yourself? Are you handy?
For digging: mini excavator and shovel. Drain pipe is a joke in terms of material.
Anyone can knock off plaster. Which one is actually meant there?
Drainage is just gravel, fleece, pipe with a slope.
For sealing, I would have to look it up.
You’d then be at maybe 1000€. You could directly insulate the side for a few more euros if it’s open anyway.