How to waterproof terrace for gardening ? You want a terrace garden. But you are also scared of one thing — water seeping into the slab and leaking into the flat below. In Mumbai, Navi Mumbai and Thane, this fear is very real.  One drop of water on your neighbour’s ceiling and you get a call from the society office the same day. The good news? You do not need to break your terrace or hire an expensive contractor to garden safely. With a few simple steps and materials easily found at any local hardware shop or online, you can …