Upper exterior wall lights

[mtldesigns 46]

Speaking of lights... the exterior of my design I am using the warehouse style.  This is a small commercial build, and has a parapet wall/roof system.  I need the lights to be high on the exterior wall.  Originally, I had all the lights on my main floor plan model.. but to avoid clutter, I started to move all to the attic plan (next level up).  However I noticed that the exact same lights shown on the floor plan glow so much more than the ones copied to the attic plan.  Why is that?