Depends how he is hogging. Torrenting can be a pain as it saturates the upload, which causes problems for the download, and everyone in general. I had someone who was doing this consistently on a wired connection a while ago (connected to a Draytek router) and on those, you can rate limit each ethernet port, both in and out independently, so I tweaked his port on the "in" side only (which is his upload), lowering to 1KB / second. Yup, that fixed everyone's issues, and still allowed him to browse (download) at a reasonable speed.
You could get an alternative access point (if he's using wireless) that supports limiting and make him use that instead (wired into the home hub) - but they are always going to match on IP address (poor) or client MAC address (also poor, as they can be changed to anything, unless of course, you lock down the AP to only allow his client MAC to associate).
Or, alternatively, you can buy a managed ethernet switch like I got myself a while ago (a netgear prosafe plus 5 port gigabit) - these are surprisingly nifty as they allow you to rate limit each ethernet port (like the DrayTek I spoke of earlier) but without all the additional wireless/broadband modem/router integration (they are simply a switch). Then plug a standard AP into the rate limited port on that, linking it back to the home hub, lock him to that AP, job done.
PS - yeah, it seems like the home hub 3 you have can't do what you are wanting: https://community.bt.com/t5/Connected-Devices-Other/...