ᐅ Drainage channel beneath the wear layer?

Hello!

We will be paving our terrace above the base layer, so it won’t be at ground level. Would you still recommend installing a drainage channel beneath the base layer?
If yes, would a simple infiltration system using a corrugated pipe with gravel be sufficient, or should it be connected to the main sewer system?

Thanks for your help.

As long as you are deep enough below the threshold so that no standing water pushes through the patio door and you have a slope away from the house, I would skip the gutter.