Make every wire dead before you touch it: switch off all breakers and every generator, solar and battery source feeding the building, confirm with a tester that nothing is live, and only then pull cable from the outlet end and cut it free. Strip insulation with a knife or strippers, never by burning, because the smoke is toxic, and treat old solder joints on pipe as possibly lead-bearing.
Part of Building Material Recovery
Copper is the most valuable recoverable metal in most buildings, because it conducts electricity and heat, resists corrosion and is easy to work. It also sits behind the walls beside the building’s most dangerous energy.
Copper Is Worth The Work Only If The Wiring Is Dead
Electrical cable (Romex, or NM cable) runs through walls, attics and basements and contains two or three copper conductors in a plastic jacket. Copper pipe (Type L or Type M) carries water. The parent article warns that wires may be energised if any local power generation exists. A solar array makes power whenever the sun shines, a battery bank holds it, and a generator can feed the building, so the grid being down does not make the wiring safe.
What You Need
- A voltage tester, a non-contact tester if available.
- Knife, wire strippers, side-cutters, a hacksaw or pipe cutter.
- Insulated gloves and eye protection.
- A torch or heat source and a heat shield (a sheet of metal or wet rags) for solder joints.
- Sorting bins for clean copper, insulated wire and pipe.
Method: De-Energise, Test, Pull, Strip
Step 1: De-energise. Switch off every breaker, including the main. Switch off and disconnect any generator, solar array disconnect or battery bank connected to the building.
Step 2: Test. Confirm with a tester that outlets, switches and the panel are dead. A tester must be checked on a known live source first, or it proves nothing. If you cannot confirm that a circuit is dead, leave it.
Step 3: Remove device covers (outlet and switch plates), disconnect the wire from the device, and pull the cable from the panel end where the cable allows, as the parent article describes. Do not cut the service feed unless it is proven dead.
Step 4: Cut cable free at accessible points. Cut only cable you have proved dead.
Step 5: Strip. Remove insulation with a knife, cutting away from the body, or wire strippers. Clean copper is worth more, for conductivity and trade, than insulated wire (parent article).
Step 6: Copper pipe. Shut off and drain the pipe. Cut with a pipe cutter or hacksaw. Solder joints can be separated by heating with a torch until the solder melts, then pulling the parts apart (parent article).
Step 7: Sort. Copper pipe is useful for plumbing, still construction, heat exchangers and condensers (parent article).
Common Mistakes
- Cutting the main feed first. It may be live; prove it dead.
- Burning off insulation. The smoke is toxic; strip by hand.
- Heating a pipe joint beside wood. Flame and conducted heat ignite framing.
- Assuming all copper pipe carries water. Some carry gas or fuel; see below.
- Hauling cable hard through the framing. It jams and snaps; free it at accessible points.
Safety
Live wires, toxic smoke, gas pipe and hot solder
Mains electricity can kill; so can the output of a solar array or battery bank, so treat everything as live until tested. Do not burn insulation to free the copper. A pipe may carry gas or fuel: if you smell gas, stop, ventilate and do not use a flame or spark, and never test for a leak with a flame. Older solder on plumbing joints may contain lead, so heat in the open air, do not breathe the fume, and do not reuse such pipe for drinking water. Keep a wet rag or sand beside any torch work.
What’s Next
- Learn next: Glass, Hardware & Insulation — the next group of materials
- Combine with: Copper Wire — what recovered copper is used for