I wasn't really sure what sub-forum this belongs in so I guess I'll ask here. My stoop is covered with a gable roof, soffit under the overhangs, and about a 2' vertical wall (LVL supporting roof trusses) that will get bricked on both sides. On the inside ceiling there's 5/8" OSB. I'm going to put up vented aluminum soffit to match the rest of the house, but I'm not sure how to attach it. Do I have to put up 2x runners in the middle to staple to and f-channel along the outside, or can I just staple it directly to the OSB and lose the channel since the brick would cover that anyway?