wall surface; surface of a wall
Refers to the flat face of a wall, often in architectural, artistic, or descriptive contexts.
A large painting was displayed on the wall surface of the museum.
Ivy grows all over the surface of the building's wall.
I decorated the wall surface with a lot of photos.
We mounted the air conditioner on the wall surface.
The workers painted the wall surface white.
This building has extensive wall-surface greening.