Network layout help (switch redundancy)

Greetings,

I am designing a network for my organization's new building and I am hoping to build in redundancy from the access switches to the core and firewall (see diagram).

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I'm struggling to understand the best way to create redundant "uplinks" to the core from the access switch stacks, without creating loops. Is LAG/LACP the best practice for this? The switches are mostly Aruba 2930F.

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Here's an example: the Floor 2 IDF has a stack of (3) 2930F switches. Two of those switches have an uplink back to the core switch stack (2x 2930F switches). If all switches are operational, would this create a loop?