Remove waste room that is cast with house

[Martin_355]

Hello. A craftsman has drained around the entire house, and moisture is coming in through one of the basement walls. It is behind the garbage room (the room is 1 meter high).

To fix this, the craftsman wants to chisel up part of the room and only have a ledge 10 cm up where the room starts and 10 cm down where it ends. He will put up moisture-proofing boards there.

The reason he didn't do this from the beginning was that he considered the house's construction/slope. If it would damage the house's structural frame. I hope you understand what I mean.

My question is, can you chisel up the room without damaging the house's properties/construction, as the craftsman suggests?

The house is from 1965 and is a brick house with plastered walls. The room is cast with the house. I don't want anything else to be damaged.

 

[Testarn]

It's a bit difficult to understand what it looks like today, can you upload some pictures/sketches?

Pordrän should be on the outside of the wall and not on the inside.

 

[Martin_355]

Hello. Made a quick sketch. It's in front of the garage. Concrete stairs going down that are not visible due to the bush. Drainage pipe in front of the new wall.