Actually.......doing higher rep's (10-15 and sometimes, for special goals, 20 reps) can be an excellent way to build body mass. With perhaps sets of 2 to 4. Going to get a whole new feel and experience with those higher reps and get stronger,
In the superior compound lifts, like DL's, squats, cleans, jerk presses, etc, you will encounter stamina (strength plus endurance) issues at first, even with light to moderate weight. Which can be quickly adapted to by the body. You are not just working out , but training the body to a higher degree of performance. In return, gaining muscle mass and improved power in any lift you choose. Might suggest, never go to the point of failure on any set, even the last one. Good Luck.