Lights going through wall

Hello,
Is it any way to avoid

? I have a room with a point light illuminating the room, the problems is when I move outside the room I can see the indoors light lighting the opposite side of the wall as well as the water surface floor outside the room.
A attached some images as references.
I will appreciate any help.
Thank you.

Use layers and culling masks so the light only affects the interior of the room.

You have to have Unity Pro and enable Shadow casting. Without shadows, you’ll get what you see.

Make the water layer say water and turn off the water layer on the light that way it doesn’t show up on the water.

One option in Pro is to switch to a perspective camera with an small viewing angle e.g. 17.