Several points:
1) If the bowtie size was 7 inches, then you have a too-small design. Consult
this site for more appropriate designs.
2) Bowtie antennas are not very sensitive to channels 2 - 6. Remember that digital 4.1 is actually broadcast on channel 25.
3) TV signals travel generally by line-of-sight. You will lose a tremendous amount of signal by trying to pick up signals in the basement. Locating outside is best, but the attic should work.
4) There are other DIY antennas that will work better than your bowties. However,
5) Consult with the OTA forum at digitalhome.ca for better targeted advice.