Hello! I'm trying to help out my brother whose bathroom was remodeled about two years ago. Location: Los Angeles.His new shower has a small "shelf" in it, and a grout crack (approx. 1/8 of an inch at its widest) has formed all around it. (The shower itself has only been used once or twice so far.) The shelf is not wobbling, it's very sturdy.PICS HERE: http://bit.ly/2Qkgnrb idea why the crack happened? (Was it poor workmanship by his contractor?)What's the solution (just add more grout)?Should we put some kind of backer rod in the crack first?Will more grout be enough to waterproof seal the crack?THANK YOU IN ADVANCE! : ) via /r/DIY http://bit.ly/2WTtoKq
