I am in the beginning stages of remodeling my unfinished attic for a nursery and small office. After starting to insulate I realized my floor joists we true 2x6's that spanned 20 feet at their widest point. The majority of the room, the span is 15 feet. The room is obviously a bit bouncy. Should I stop and fix this, or am I okay to continue? Suggestions. I have considered sistering the joists but I have heard this is pretty complicated. Also could add a beam below, but it would not be able to be in the middle of the 20 foot span, and of course the living room below is finished.