Semi-detached house with WU cellar: How is the communication wall viewed?

Hello everyone,

we are building a semi-detached house with a solid WU basement. A large basement room is intended as a hobby room (basement 3 in the picture). Three out of four walls in this room were coated with lime-cement plaster - except the party wall to the neighbors (see photo). The party wall is also the WU concrete wall. For aesthetic reasons, we would also like to have it plastered - the question is whether this is still considered a contractual service (general contractor) or if we have to pay extra for it. The contract states: "the inside surfaces of the WU concrete basement exterior walls in the area of basement 3 will be professionally plastered with a single layer of lime-cement plaster and painted white." The devil is in the details, as always: it says WU exterior walls, and I suspect that the party wall is not interpreted as an exterior wall but as a partition/interior wall. I have submitted an inquiry, now we wait, the responsible employee is on vacation for 2 weeks. Do you have tips and experience regarding this wordplay? How is this wall viewed from an expert perspective?

Thank you!
Regards

we are building a semi-detached house with solid WU basement. [...] I suspect that the party wall is interpreted not as an exterior wall, but as a partition/interior wall.

The term exterior wall refers to a building, not to a group of houses. Party walls in the traditional sense (shared / single-layer) have not been newly built for a long time. Water can also penetrate the gap between the two exterior walls and should be kept out of the building fabric. "Kind of pregnant" does not exist - just as little as "WU on one side only". Differences in interpretation between client and contractor do not exclude this, of course. Accepting a surcharge for this position will be cheaper than a legal dispute.

Applying plaster there is no effort for the plastering team. Talk to them on the construction site.