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AI BUILDERS Electric

Service

Subpanel installation and upgrades

A subpanel puts circuits where the work is, instead of running every branch back to the main panel. It is the usual answer when a garage, addition or workshop needs more than one or two circuits.

When a subpanel is the right answer

If you are adding a garage workshop, converting space into an ADU, or building an addition, you are usually adding several circuits at once. Feeding each one individually from the main panel means long runs, a crowded panel and voltage drop over distance. A subpanel takes one properly sized feeder to the new area and distributes from there. It is normally cheaper than the alternative, it leaves room to add more later, and it makes the finished system far easier to understand when somebody has to work on it in ten years.

Sizing and feeder design

The part that matters most happens before anything is mounted. We calculate the load the subpanel will actually carry, check what spare capacity the main service has, and size the feeder conductors for the distance so voltage drop stays inside limits. A long run to a detached structure often needs larger conductors than the breaker size alone would suggest. We also work out the grounding and bonding arrangement, which is different for a detached building than for a subpanel inside the same structure, and is one of the details most often got wrong.

Detached structures

Garages, studios, pool houses and ADUs bring a trench, a conduit route and a decision about whether the structure needs its own grounding electrode. We walk the route with you before quoting, because the trench is frequently the largest single cost and the path affects it more than the length does. Where a structure already has power that was added informally over the years, we will tell you honestly whether it can be extended or whether it is better replaced.

Common questions

Do I need a subpanel or a bigger main panel?

They solve different problems. A subpanel adds circuit spaces and puts them near the work. A service upgrade adds total capacity. If your main service has spare capacity but no spare spaces, a subpanel is usually cheaper. If the service itself is maxed out, a subpanel will not help and we will say so.

Can a subpanel go in a detached garage?

Yes, and it is one of the most common reasons to install one. It needs a properly sized feeder, a trench and conduit along the route, and its own grounding arrangement. We work all of that out at the estimate stage so the price you see accounts for the trench rather than discovering it later.

How many circuits can I add?

That depends on the subpanel size and, more importantly, on what the circuits will carry. A workshop with a welder and a dust collector demands very different capacity from a garage with lighting and a couple of outlets. Tell us what equipment you plan to run and we will size it for that.

Call (800) 280-0428

Tell us what your property needs

Planning a garage, ADU or addition? Call (800) 280-0428 for a free estimate on the subpanel and feeder.

(800) 280-0428 Call (800) 280-0428