thatwasawkward-abiography:

Darth Vader: wears mask to hide severe and gruesome disfigurement from falling into a pit of lava, aid with speech and breathing

Kylo Ren: wears a mask literally just because he’s dramatic

I did notice while watching that it appears a bit beaten up, so maybe it does have some practical value. But it could also just be that he’s thrown it across the room. I feel that the more we learn about The Force Awakens, the more of a gift it is.