Adjusting transparency of V-ray glass materials?

[galrot]

Hey.

I have recently started to use V-ray for sketchup but I am really struggling on how to adjust the transparency of the vray glass material in the material editor. I want it to become less transparent so that it is not that visible that my city model does not have interiors. I've searched around, watched many tutorials and played around with the settings, yet I can't seem to grasp how to adjust it. Could anyone explain to me (like I am five ) how I edit the transparency of the materials in vray?

[filibis]

Hi,
Refraction parameters and Opacity map values effect transparency. Take a look at this: VRay Material | VRayBRDF