My one year old doesnt talk much, should I be worried?

My sons 13 months and doesn't talk much. He says hi,mama,dada,Baba..... But no real words. I try and talk to him alot like if im changing his diaper I'll say diaper change, if he's getting ready to eat I'll say eat, when I read I say book and so on. My roommates son is 2 and doesn't talk at all just grunts and yells. Im starting to get concerned that because he's not talking my son thinks that he shouldn't either.... Just wanted to know what other ppl thought. No ignorant, non helpful feed back please and thank you!