Should I be leaving a service loop for my subpanel feeders?

There isn't a specific code requirement in the NEC that mandates a service loop for feeders in a subpanel. As long as the wire isn't under tension and you've respected the **minimum bending radius** for that 2-gauge aluminum, going from point A to point B is perfectly legal. If the wires aren't pulling on the lugs and the panel looks clean, you've met the basic requirements.

That said, many guys lean toward leaving some slack. The big reason is future-proofing. If a terminal ever overheats or the end of the wire gets damaged, you want enought length to cut off an inch or two and re-strip it. If you cut it exactly to length now and somethig happens later, you’re stuck either pulling new feeders or using expensive Polaris taps to splice on an extension, wich can be a real headache.

I usally prefer to run the feeders around the perimeter of the enclosure before landing them. It keeps the center of the panel open for your branch circuit wiring and gives you that extra bit of wire for repairs. But it’s ultimately a preference thing. Some guys hate the look of extra wire and think it just clutters up the gutter space where the smaller branch circuit wires need to go.

Since you're working with aluminum, the most important thing is using a **torque wrench** to hit the specs on the panel label. Aluminum expands and contracts more than copper, so those connections need to be spot on to prevent arcing over time. And make sure you use an anti-oxidant paste if the lugs require it. If you've allready landed them and they aren't under physical stress, I wouldn't bother re-doing the work just to add a loop.

I'm curious about the 'gutter space' you mentioned. Is there a specific rule for how much room you have to leave for the smaller wires? These 2-gauge feeders are so stiff that I’m worried if I loop them, I’ll end up blocking the knockouts for my other circuits.

Also, for the torque wrench, do I find the specs on the door label or the lugs themselves? I usually just hand-tighten until it feels 'good,' but I definitly don't want to guess with aluminum since I heard it's more temperamental.

Definitely don't trust the 'hand-tight' feel, expecially with aluminum. It’s prone to cold flow, meaning it’ll actually compress and loosen up over time if it’s not torqued to spec. You’ll usually find those torque values on the main label inside the door or sometimes stamped right on the side of the lugs.

On the gutter space, just watch that you aren't crowding the box so much that you can't see your terminations. If the wire is too stiff to loop without blocking every knockout, I’d stick with the direct run. Just ensure there’s no 'spring' tension pushing against the lug, or you’ll end up stressing the plastic insulators on the bus bar over time.

One thing to watch out for if you go the loop route is the depth of the enclosure. I've seen guys leave a massive service loop only to realize the 2ga aluminum is pushing back so hard they can't get the dead front cover screwed on. If you decide to loop it, use some offset bends to keep the wire pinned against the back of the tub. It keeps things way more manageable when you start pulling your branch circuits. Also, if you use zip ties to keep it tidy, just make sure they aren't super tight—you just want them to hold the 'memory' of the bend.