Romex, THHN and BX: What to Do With Leftover Wire

Every electrician, remodeler, and weekend rewirer ends up with a bucket of leftover wire. It's usually a tangle of white jacketed cable, colored single conductors, and some stiff armored stuff, and it all gets tossed together. Winco Scrap Metal & Container's wire page is a good checklist for what's in that bucket. It lists copper wire in low and heavy grades (including No. 1 and No. 2), Romex, Rainbow (THHN), steel BX, aluminum BX and aluminum-insulated cables, and RF cables.

Know what you're holding

Start by naming each type, because they don't all go in the same place.

• Romex: the flat, jacketed cable from house wiring, usually white or yellow. A plastic sheath wraps several insulated conductors and a bare ground wire.
• THHN: single insulated conductors, often pulled through conduit. They come in colors, which is why Winco's page calls it Rainbow (THHN).
• BX: armored cable, a flexible metal jacket wound around insulated conductors. Steel BX has a steel armor. Aluminum BX has an aluminum armor.
• RF cables: the coax that carries antenna and cable signals.

Two quick checks sort most of it. First, use a magnet. Steel armor sticks to it, aluminum armor doesn't. Second, scrape the end of a conductor with a knife. Copper shows an orange-pink shine. Aluminum shows a silver-gray one. Large cable from a service entrance is often aluminum, so don't assume heavy wire means copper.

To strip or not to strip

Stripping means taking off the insulation so you're left with bare metal. Winco's copper page lists both stripped copper wire and insulated copper wire, so you can bring either one. The real question is whether your time is worth it.

For a few feet of cord, stripping is almost never worth the effort. For several hundred feet of Romex from a house rewire, it might be, and that's a call worth making with the yard. Ask how they'd assess your wire insulated versus stripped. The technicians who weigh and assess loads see this every day and can tell you what makes sense for your amount. Then you aren't spending an evening with a utility knife for nothing.

If you do strip, use a real wire stripper or a cable-ripping tool instead of cutting toward your hand with a blade. Slice the jacket lengthwise, peel it back, and pull the conductors out. A cheap bench-mounted stripper is the kind of thing that pays for itself on a big rewire, but only if you have the volume.

Keep the piles separate

As a rule, yards want different metals apart. A bucket that holds copper Romex, aluminum service cable, and steel BX together is a sorting job for somebody, and it can drag the whole bucket down to the lowest grade. Use three or four containers if you have to. Here's a simple split:

Copper wire goes in one, with the heavy stuff apart from thin, small-gauge wire since Winco lists low-grade and heavy-grade wire separately. Aluminum cable goes in another. Steel BX goes in a third. RF cable and everything else gets its own. Pull out connectors, wire nuts, plugs, and boxes first, since those are mixed metals and plastic that don't belong with clean wire.

Mixed-up wire also slows you down at home. If you work out of a van, keep a marked bucket for each type under the shelf and drop offcuts in as you go, so the sorting happens in ten seconds on the job instead of an hour in the garage on Sunday. A homeowner can do the same with three cardboard boxes and a marker. When the boxes fill up, you're ready to drive.

Getting it to Moosup

Coil the wire and bundle it with tape or a zip tie so it doesn't turn into a rat's nest on the scale. A dry five-gallon bucket works for short lengths. For a long run, a few tied coils in the truck bed is easier than loose cable. Don't overfill any container you have to carry; wire is heavier than it looks.

Winco has a 35-foot truck scale on site and accepts large truckloads of recyclable metal, so a contractor with a full load of cable is a normal customer. A homeowner with one bucket is a normal customer too. Tell the staff what you've got when you pull in and they'll show you where to go.

Hours are Monday through Friday, 8:00 AM to 5:00 PM, and Saturday, 8:00 AM to 2:00 PM. The yard is closed Sunday. If you're not sure whether something counts as copper, aluminum, or something else, bring a short piece and ask.

Winco's wire recycling page lists every type of cable they take. Call (860) 230-0552 with questions before you start stripping.