I used just a random wire down the peak of my attic, when I first got into this.
The noise was terrible; only pirate I could get was WHYP... but that of course was not a balanced antenna with a coax lead, so I guess the noise would be higher. No matter what, any antenna inside an attic is going to be a compromise... much better to be outside in the clear.
On the other hand, on the transmitting side, I once tied both sides of my 90m dipole together and ran it as a "single wire T" into a tuner, for 1710 kHz, effectively making the 35 ft of coax in the attic into the first part of the antenna. The greater part of the antenna was outside, but the first part was along the peak of the attic. I was logged (unid) with "strong signal" some 460 miles away in Pennsylvania, "blowing away Lubavicher at times". Ground consisted of some buried radials , ground rods, and the house's furnace duct system.
That system seemed to work better than a triangular dipole setup for 1710, but hung way too low for the frequency.
Gonna have to try that again, one of these days...
John Poet