Rated Battleground Challenges

Here are the criterias for making it a guildrun;
4/5 - dungeons
8/10 - 10 player raid, 10 player BG
20/25 - 25 player raid, 25 player BG
10/40 - 40 player raid
12/15 - 15 player BG
2/2, 3/3, 5/5 - Arenas

Can someone supply information about requirements for rated battlegrounds. Our guild leader is under the impression that we can qualify for the rated battleground weekly quild challenges with L19s. But I've heard that rated requires L85s.

I've never done a guild run except to a 5-man dungeon and we did it with 3.