Thank you for your question regarding the testing of Ufer grounds on homes. It is our pleasure to help.
The term “Ufer” ground is another word used to describe what the National Electrical Code (NEC) calls a “concrete encased electrode”. It is also commonly referred to as “building steel”. Whatever you call it, we are talking about the rebar in the concrete foundation. Here is a link with some additional information you may find useful:
Testing a concrete foundation (Ufer ground) is virtually impossible to do with the exception of when the foundation has been originally constructed. Once water pipes, electrical systems, Telco grounds, Cable TV grounds, gas pipes, sever lines, etc. have been connected to the home, it is impossible to test the resistance-to-ground of the slab. Sorry to be the bearer of bad news, but the best you can do is to model the system in a computer. This is actually a very reliable technique which merely requires soil resistivity data to complete, but it is not a direct test one can simply hit a button on a meter to see the result.
The only other thing that can be done is to conduct 2-point resistance (continuity) measurements around the foundation to see what the difference in potential is from one corner to the next. Of course, this would require exposed rebar, something you won’t have on the typical home.
We hope you find this information useful, if you should have any further question or would just like to speak with someone about this subject, please do not hesitate to call us at 310-318-7151 California time, and someone will be happy to speak with you free of charge.
The Engineering Team at E&S Grounding Solutions
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