I am going to extend my house to the backyard, adding a family room. I plan to add big windows(including a bay window facing the backyard) to two sides of the family room (facing side yard and backyard). My dilemma is: I could either add a 18x18 or a 27x18 square feet family room. If I add 27x18, One Side of the family room window wall is only 5 feet away from the side fence (which is 7 feet high, going to block some lights to the family room). The side fence is at east side of the house, and the ceiling is 9 feet high. I like lots of natural light in the family room, which one of the following I should choose then? Thx!