Signal loss in the attic is difficult to predict. Try a temporary setup at different locations in the attic before drilling any holes. If it doesn't work, add a preamp. If it still doesn't work, you will have to go outside. Try the Winegard HD7694P antenna.
You have some strong local FM signals that
might cause interference to TV reception; an FM filter
might be needed.
http://www.fmfool.com/modeling/tmp/1...7/Radar-FM.png