Faraday cage to block cellphone/Wifi?

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Discussion Overview

The discussion revolves around the feasibility of constructing a Faraday cage within a house to block WiFi and cellphone signals. Participants explore the implications of using chicken wire on walls, the impact of uncovered windows, and the effects of electrical wiring on the shielding effectiveness.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants suggest that using chicken wire on walls could create a Faraday cage, but express concerns about openings and electrical wiring degrading its effectiveness.
  • There is a mention that welding the seams of the wire mesh may be necessary for a continuous conductor.
  • One participant doubts that extensive coverage is needed to achieve significant signal reduction, citing that good radios can function with considerable signal attenuation.
  • Another participant shares personal experience, noting that their phone works in a shielded room unless all openings are sealed, but it drains the battery due to increased power usage.
  • A participant raises a question about the attenuation required specifically for cell phones and WiFi, indicating uncertainty about the necessary levels.
  • One participant mentions their intention to use chicken wire for plastering in a straw bale building, considering the potential additional benefit of signal blocking.
  • A humorous remark is made regarding the need for Faraday cages in university washrooms, indicating a light-hearted take on the topic.

Areas of Agreement / Disagreement

Participants express various viewpoints on the effectiveness and practicality of using a Faraday cage in a home setting. There is no consensus on the necessary coverage or the effectiveness of the proposed methods, indicating ongoing debate and uncertainty.

Contextual Notes

Participants highlight limitations such as the impact of openings and electrical wiring on shielding effectiveness, as well as uncertainty regarding the specific attenuation required for cell phones and WiFi signals.

Philippe Elskens
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Hi,
I was wondering if I could make my house a big Faraday cage capable of blocking Wifi and cellphone signals from the outside by covering all of the inside walls with chicken wire? How big of a problem is it that windows would stay uncovered? Or that electrical wiring inside the wall (so outside of the F cage) would come inside to the wall sockets (so penetrate the cage)?
 
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Philippe Elskens said:
Hi,
I was wondering if I could make my house a big Faraday cage capable of blocking Wifi and cellphone signals from the outside by covering all of the inside walls with chicken wire? How big of a problem is it that windows would stay uncovered? Or that electrical wiring inside the wall (so outside of the F cage) would come inside to the wall sockets (so penetrate the cage)?
Welcome to the PF.

Openings in the shield degrade its effectiveness, and any wires that come in from outside without being filtered will also degrade the shielding effect. Also, you would need to weld the seams of the wire mesh where they come together, in order to have a good continuous conductor. Look at these shielded rooms:

http://www.ets-lindgren.com/RFShieldedEnclosures

Is there a reason that you don't want to have cell phone or WiFi reception inside your home? :smile:
 
Philippe Elskens said:
Hi,
I was wondering if I could make my house a big Faraday cage capable of blocking Wifi and cellphone signals from the outside by covering all of the inside walls with chicken wire?

berkeman said:
Is there a reason that you don't want to have cell phone or WiFi reception inside your home? :smile:
looking forward to a response to that as well :wink:Dave
 
davenn said:
looking forward to a response to that as well :wink:Dave

Obviously he's developing an 802.11 chipset... :wink:
 
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berkeman said:
Openings in the shield degrade its effectiveness, and any wires that come in from outside without being filtered will also degrade the shielding effect. Also, you would need to weld the seams of the wire mesh where they come together, in order to have a good continuous conductor. Look at these shielded rooms:

I doubt that you need anything like that kind of coverage in order to get a big reduction in signal strength.
 
bcrowell said:
I doubt that you need anything like that kind of coverage in order to get a big reduction in signal strength.
Most good radios that I'm familiar with can work reasonably down to -70dB from full signal strength. That's a lot of needed attenuation to block a signal.

TBH, I don't know how much attenuation is needed for cell phones and WiFi though. Guess I'll do a little searching... :smile:
 
bcrowell said:
I doubt that you need anything like that kind of coverage in order to get a big reduction in signal strength.

You'd be surprised. My phone works reasonably well inside our shielded room unless absolutely everything is closed and properly sealed. Even the small hatches we sometimes use to get temporary cables in/out of the room need to be sealed up.
Having the phone on inside the room DOES drain the battery of the phone since it needs to increase the power it uses; but it does work.
Phones and WiFi uses all sorts of tricks to get a good connection even under very bad conditions.
 
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f95toli said:
Phones and WiFi uses all sorts of tricks to get a good connection even under very bad conditions.

but it still can't get 15 - 20m range from one side of my home to the other, with only a couple of dry walls in between ... go figure ??Dave
 
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Hmm, ok, thanks for the answers!

My plan is to construct a straw bale building. It is recommended to use chicken wire on the walls for plastering. So that is the reason why I'm doing this:-) I was just thinking that it might act as a Faraday cage, which could be an additional advantage with regard to possible health effects...
 
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I would like the washrooms at my university to be enclosed in Faraday cages.
 
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