Plans for an addition to my home, include crossing an existing stem wall concrete footing with a new footing near one corner of the existing structure. I suppose this is to "tie" the new structure with the old as well as provide a stronger footing support for the new second story which is over this part of the addition. My question is, does the new footing simply butt up to the old footing on either side, or do I need to remove or channel the old footing to allow the new footing to cross? I hope that is clear to understand. Other parts of the footing plans call for underpinning the old footings, and also there are several areas where large pads of concrete will be underpinning the new footings as well. I think this footing design is a bit "over" engineered, but maybe its because there are no steel beams used on this 2nd story addition.