Glass Material for HTC Vive VR experience

Hello,

I am trying to create an architectural scene. I want to create a glass material which will not be heavy on the system. As you can see in the attached image, the shader complexity shoots into red with a ‘translucent’ blend mode. I need to have multiple windows, glass doors and walls in my scene which would hamper performance if this type of material is used. Please suggest any alternate technique which would help give the effect of glass without taking a toll on the performance.

Thanks.
Amey.