First, unless you try the antenna in the attic, you can't be sure the attic will be a good reception site. Construction materials can include metal and other base materials that may impair reception.
If your attic is a reception friendly site and depending on how much room you have in the attic, an Antennacraft HBU-33, 44 or 55 could provide plenty of signal power to drive a passive 8-way splitter. If you need to move the antenna out of the attic, the Antennacraft is fairly easy to re-fold without damage.
Ideally, you would use only one splitter, with exactly the number of ports needed. By doing so, you'll keep losses to a minimum. 6-way splitters exist:
http://www.3starinc.com/holland_6-wa..._splitter.html and if you have a couple of very short runs, you may also consider a 4-way splitter with a 2-way splitter fed off a port. The 2-way would have lower output so it would be the source for feeding the shortest cable runs.