For those who want no electromagnetic radiation in their homes, perhaps this new window film would help: CPFilms Llumar Signal Defense--the latest in EMF-blocking paints and covers--is designed to pass light but not signals. The idea is that by putting this film over windows, companies can keep their networks more fully enclosed. (Walls might need special paint, or might have enough material already blocking transmission.) The company says it's been making the film for several years for government purposes, protecting over 200 federal agency buildings. The film is also blast-resistent, and reduces fragmentation in case of an explosion or break-in.
Ostensibly, someone attempting to prevent signals from entering their homes, could apply this to their windows, too, serving the opposite intent.