That seems like a big antenna for the job. You certainly wouldn't need that much outside. The attic will have some impact though. Are you sure you have room in the attic for it? I'd think about the HBU-22 instead. A lot more maneuverable and should pull pretty well. Think about roof materials - metals, foils, etc make a nice Faraday experiment. Also consider trees nearby. NW is pretty much your direction, but consider that it may tune better at off angles due to being in the attic. I have one small antenna in the attic for a single station and I was surprised to find a better signal strength about 15 degrees off what I expected. If only we could turn on visible RF and watch it come bouncing in!
