Best way to add a color strip to wall texture?

I’m a new UE4 user, and I’m trying to create a basic high school environment for my first project. I’m working on the walls, and I currently have a generic white-painted cinder block tileable texture. I’m trying to add a color strip around the top of the walls, just as many other high school might do to “brighten” up the setting.

My question is: what is the best way to go about doing this? I have tried using decals, and it works, but I feel as though there is a better, more efficient way to achieve what I am going for.