Certainly you can get a few db attenuation, but it's absolutely not possible to block all EM radiation with a cheap layer of paint. Regarding "not treating the

Certainly you can get a few db attenuation, but it's absolutely not possible to block all EM radiation with a cheap layer of paint. Regarding "not treating the the floor", how to you prevent reflections? If there's any metal beneath the floor it will reflect the signals into the room. Whatever, if your meter is reading "less than background" then it is clearly misleading you.