Just as I finalized my window order, after weeks deciding on grids,etc. I discovered that the new construction wood windows I am ordering don't have nail fins. I decided on new construction windows as my house is pretty much gutted, also opting not to get brick mold as going to try and interface with existing siding. Now I'm not sure what makes these different from replacement windows, and how they get attached without nail fins. Can anyone guide me to a site that shows how these window are installed. Some contractors attach the trim before setting window, I'm just have a hard time visualizing how this will work.