Exterior rendering backgroundtchup background externsions

Why is my background showing up on my exterior windows?
This is my SU Model

This is the rendered image. The background is showing through a wall and the front windows.
Glass is set to translucent grey/common

What do you mean? Show an example. Is this in SketchUp that you are seeing it or something else?

Are the windows transparent? It seems you could be looking right thru your model at the background.