Footer bonds and load calcs.

[allenwayne]

In all but one of the nearby municipalities we work in,we are required to have a footer bond that is signed off by building inspector when they do slab /footer inspection.We have just recentley adapted this method of service grounding.My question is this,since 250.66 requires us to size the grounding comductor to ungrounded incoming service feeders.What if a spec home gets upgrades/extras after the fact and new load calc goes into 400 or up service?
So far this has not come up as an issue.AHJ`S have allowed the #4 we use from footer to be the gound for 400 amp services

 

[iwire]

Re: Footer bonds and load calcs.

250.66(B) Connections to Concrete-Encased Electrodes. Where the grounding electrode conductor is connected to a concrete-encased electrode as permitted in 250.52(A)(3), that portion of the conductor that is the sole connection to the grounding electrode shall not be required to be larger than 4 AWG copper wire.