It's not clear why you have chosen to mount in the attic. FWIW, the FCC prevents HOA rules and zoning regulations from interfering with your choice:
http://www.fcc.gov/guides/over-air-r...ces-rule#links
Metal and tile roofs make for very poor reception. Foil faced insulation also interferes a great deal.
If you have a wood framed roof and composition shingles, and choose to install in the attic, you'll want to use a fairly high gain antenna array.
I would suggest an Antennas Direct DB8 facing about 155° and an Antennacraft Y10713 pointing at 204°. Combine the two antennas using a UVSJ. The output of the UVSJ would feed a 2 port DA (CM-3412).
http://www.amazon.com/Antennas-Direc...1&keywords=db8
http://www.amazon.com/Antennas-Direc...&keywords=UVSJ
http://www.antennacraft.net/Antennas/AntennasVHF.html
http://www.amazon.com/PCT-Internatio...eywords=CM3412
Depending on roof construction, CW may not be reliable.
Outside in the clear, you'll have stronger and higher quality signal available. (Strength and quality are not synonymous.)