Grubby is good!
Tho' I've spent bits of time in the US, Canada and Africa, most of the buildingsI know are European and definitely GRUBBY!!!! (especially Scotland!) The kind of sunny, spotlessly clean walls and floors provided default in the Sims2 game aren't real to me! ;)
I make different walls and floors for most of my new buildings, and I hope you enjoy how grubby they get near the ground!!! :)