Just slapping on a coat of the stuff would not work, but doing it correctly absolutely does work. It takes a few coats and you have to ground it. Done correct

Just slapping on a coat of the stuff would not work, but doing it correctly absolutely does work. It takes a few coats and you have to ground it. Done correctly, you won't be able to use Wifi or make a phone call. Yes you will get some leakage from windows, but that can be attenuated with metal screens or use steel roll-down shutters that have the benefit of improving the R/U insulation rating of the windows at night and improving physical security. I have tested this in two houses. I will also be adding the paint to a property I recently acquired. If you bookmark this thread, I will circle back in about six months after the snow to test the attenuation.