Is it possible to see inside a house if you have external illumination?

Question

I was told that if you have a wall of windows that you can't see inside if there are exterior lights aiming downward stretched along the overhang/soffit

Answer 1

It will depend on the amount of illumination outside of the house versus the light level inside. Which ever side is brighter will be the side that will be visable from the other. This is the principle behing the "sunscreen" shades you find in fast food restaurants or in other sunrooms. If it is bright and sunny outside and dimmer inside, you can look out the sheer weave shades, but you can't see in. At night when the light levels flip flop, the opposite happens. Just think of walking down the street at night and how visable living rooms etc. are in well lit homes from the street, and how when you are inside those rooms, you can't see out, you see your reflection.
I would recommend doing some research with a reputable lighting store to find out how much exterior illumination would be necessary to outshine the interior light level, so this result can be accomplished.

Answer 2

As long as the outside lights are noticeably brighter than the inside, a casual observer will not be able to see in.