The exterior color is called Kessler Brown 40 from Caparol. However, it has nothing to do with brown. The color looks different depending on the lighting conditions, ranging from almost white in sunlight to gray when it is overcast.
Do you mean Kassler Brown 40.
According to Caparol, it has a brightness reference value of 57, it looks lighter on your side. Do you have more pictures?
Unfortunately, my desired gray-brown does not exist.
An alternative would be chocolate brown. Or wood foil, the window maker only uses Renolith foil. The price is about the same as anthracite. With chocolate brown, there would also be matching roller shutters. It would fit with the roof. I just don’t know if it looks too old-fashioned, but warm roof and windows in chocolate brown and cool gray on the facade somehow also fit.