hello, I need some guidance on the project that I am embarking on. I am looking to build a bookshelf in the space between the chimney and the wall in my sitting room. I do not want to make a straight forward mdf book shelf that will sag once I start to put any books on it. I tend to use MDF or Ply. The finish, I am thinking of spray painting it in white to match the walls and to give the room look spacious. How do i make the bookshelf that will take the weight of the books and will have a proffessional look? All help be very much appreciated. Thank you