Why there is no light coming inside from the window I have made the model with Archimesh addon. I want light should produce voulmetric type from the window inside the room. I have used spot as light source and strength as 100 default. But there is no light coming inside the light. What setting im missing so that light should transparent the glass windows.
Besides the glass issue pointed out by @Timaroberts your model has lots of problems The most important one is that Materials created in blender internal will not work on cycles, you need to create new materials using cycles shaders.

Then: Unconnected nodes have no effect.



Never connect nodes on a redundant loop (see the red line?)



Then you have a big box with a solidify modifier surrounding all of the "room", so that even if your materials were correctly set, that box would not let light through the glass anyway...



Fix all of that before you can have volumetrics... to set it up read this post:

Atmospheric lighting in cycles