Step2 Naturally Playful Playhouse Climber & Swing Set Extension

Q: Does the product needs to be attached to the ground? Im planning to place it into a terrace with floor instead of into grass.

You definately want to anchor this to the ground. It comes with 4 long U shaped spikes and straps that secure it to the ground. If the child swings to hard it will come up on the pavement. We built ours on the concrete patio and I tried it for sturdiness before moving it onto the mulch of the playground, it definately slides and the small end (without the house) will rock back and forth. Even now when I swing next to my son (he's one, and in the baby swing and I'm about 115 pounds) it moves a little bit and it's anchored in really good. This wouldn't deter me from buying it again since it isn't made for bigger kids (or me...)