O.K here goes I am doing a kitchen remodel and radiant heat install BUT ... The homeowner wants more space. They want to push one wall of the kitchen out about 3.5 foot, the wall is the gable wall but there is an attached garage so it already weather tight. One of their friends (a backyard DIY pro??) says it’s a non load bearing wall except for the outside walls studs/jacks. This much I agree with but he is telling them no extra support is needed no headers. Another guy says a header is needed. So here I am a confused Plumber stuck in the middle who has never run across this type of issue?? How should it be done correctly? It is a single level house the span that would be eliminated would be 12’.