I'm planning to build a metal garden shed on grass with a plastic grid.
I'm a bit concerned about moisture. What is the common practice?
The options are:
1) Lay a damp proof membrane on grass, put a grid on top, and put the shed on the grid.
2) Or should the membrane go between the grid and the shed?
For 1) I'm concerned water may go into the shed through the grid. For 2) I'm concerned the membrane may tear if we walk on the membrane as it rubs against the grid. Or do I need two layers of membrane?