Ufer on gravel bed - proper grounding

[car-son]

Hi. I'm new to the site. I need some help on a new build sfh electrical system.

We put in an Ufer as required by code. The foundation footings were placed on min 18" compacted select fill (i.e. granite gravel trucked in from the quarry), the rebar was #4 in the footing, and the same in the stem wall. There was at least 20 ft of footing rebar sitting on the gravel when footing was poured. The rebar ground rod appeared bonded properly and extended out the top of the stem wall with the electrical panel bonded to the rebar Ufer. Everything passed inspection.

The problem is after the home was completed, the grounding system may not be working as intended. We have been getting extra amperage on cable ground line, and circuits have worked then not worked, or appliances have run hot and burnt out.

As a first step, I want to put in two 10ft rods and bond to the ground node of the Ufer, but I'm not sure this is the right course to take, and I'm wondering if I should disconnect the Ufer completely and just rely on the two new grounds as the Ufer may be not on a true native soil ground, thus inadequate.

Any comments would be welcome. Thanks.

 

[Dennis Alwon]

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