I am new to the forum, But I thought this might be a great way to get some opinions for some vinyl soffit Installation. I am installing vinyl soffit that I purchased from lowes, I am cutting the soffits about 13" long this leaves 1/4" for expansion on the panels as I have read. I nailed a 2x4 along the side of the house, This is new construction, and attached a J channel to it. I then installed a 2x4 at the end of my rafters for my fascia and I installed a piece of F trim there, so my soffit will be supported at both ends, The fascia will be covered later with a piece of aluminum trim. My question is do I need to nail the soffit anywhere to hold it in place. I know the vinyl soffit panels have a lock on the ends that the other one slides into, but when I put all these together you can slide the whole piece. I'm not sure if I should put a nail at the ends or along the length of the soffit panels. With the J and F trim I really can't nail without the nail being seem. Any advice in this matter would be greatly appreaciated.