Window all glass corner

Hi Folks

i would love to Build an Window wit an seamless glass corner like Skyframe. The windows from the library have always an distance in the corner where the Wall pops out.Iwould like to avoid that. I tried to change an Window with Blender but i dont know what the gridmeasurements so i can set the Glass exactly. Does somebody know a good Tutorial or some helpful Information to this topic ?

Thanks

A.

Eample: