Bob,

You could get by with a Radio Shack discone, or a short vertical. I once
had a 46 in whip in an attic that was 6 foot at peak. If you own the home
and are prohibited from placing antenna outside you might try searching for
"stealth", "disguise" scanner antenna. I remember seeang ad for a vent
pipe antenna. I looked like the normal type of vent pipe on the roof;
only difference was that the antenna was inserted from under-neath in the
attic. You would need to cut a 2 in hole in the roof and do the pitch etc.
to prevent water from coming in.

good luck,
Mike