The sensor cables are 2.5m (8'), and the Rift cable is 4m (13'). It's a proprietary connector at the headset end (combines HDMI and USB), so you can't replace it with your own cable, but you can (usually) extend it. Some people have had trouble with extensions, but I use a set of 6' passive HDMI and USB3.0 cables to extend mine with no problems. Above 6' you will probably have issues with passive cables.
Great, thanks. I'll have to look at investing in some extensions. By passive, do you mean mean one end is male, the other is female, so it basically connects to the end of the one from the headset and then continues on to plug into your gpu?
Yeah, read up on it a little more. I'm hoping I can get away with not extending it, but if worse comes to worse, my dad's an electrician who has a few suppliers that can hook me up with some top quality extenders
How far you can extend passively seems to depend on your video card port and how strong of a signal it's sending out. Some people have used these with no issues out to 10 feet https://www.amazon.com/gp/product/B00JJ517VI but some had to add something like https://www.amazon.com/gp/product/B01GHL72XS/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
Generally as mentioned, 6 feet should work for most cards.
Are the sensor cables easily extended? Is there a maximum length I should look out for before effecting the connection? I hate having cables all around my room, so the rear sensor will hopefully have its cable routed along the edge of the wall/ceiling, but that will of course require maybe a 2m extension. Is that too much? The front 2 should be fine at 2.5m, but it's the rear one I'm concerned about.