Answered: NEC ECC: Option B. is Contractor entitled to direct fee on substituted work in the BOQ, as the original work had already included the P&G's?

You price the change on the basis of deducting the defined cost of the omitted work, plus fee, and then adding back the defined cost of the additional work, plus fee.

If the sliding gate costs more than the swing gate, then you effectively end up paying fee on the difference, but if the sliding gate costs less than the swing gate you effectively save the fee on the difference.