How do I stop my terrace garden from damaging the roof and leaking?

Roof damage and leakage are the most common problems in terrace farming and they are preventable with the right setup. First, keep containers and beds raised off the slab on bricks, stands or pallets so water drains underneath and roots never sit against the concrete. Second, ensure every container has proper drainage holes and use a draining medium with cocopeat, never let water pool. Third, if you are making fixed raised beds, apply a proper waterproofing or use a lining and a slope so water runs to the drain, not into the slab. Fourth, avoid overwatering and direct heavy roots away from the roof surface. Also check your roof can bear the load of wet soil and beds, since saturated medium is heavy. Doing this from the start avoids the seepage and dampness that ruins ceilings below. If your roof already has weak waterproofing, fix that before you set up. When in doubt about load or waterproofing, get a local mason or civil person to look before you build heavy beds.