Yes, but it can also use several channels. This plus the AC standard becoming more popular will lead to overcrowding in 5 GHz also.
2.4 GHz has 3 non-overlapping 20 MHz channels.
5 GHz has about 23 non-overlapping 20 MHz channels.
Both go through walls, so you will get interference from neighbouring apartments no matter what technology you implement. The only solutions are to use a much higher frequency, or shield your apartment walls.
http://en.wikipedia.org/wiki/IEEE_802.11ac
http://www.amazon.com/RT-AC66U-Dual-Band-Wireless-AC1750-Gig...