1#重庆人 4 J/ ^' e* f# S7 @; z 9 s: h# z, G! {' X' f( S4 G & V* R7 d( A+ Q# TIf the builder is responsible for rough grading and the certificate as per your contract signed, then for sure, your builder has to do whatever needed to get a pass, whether it is a retaining wall or anything else. Talk to your lawyer to find out.