The Pool Equipment Pad for Landscapers and Electricians

Why this matters

Around every in-ground pool runs a bare copper wire that most people never see and nobody thinks about until it is gone. It ties the pool's steel, the pump, the heater, the ladder anchors and the deck around the water into one electrical body, so that a stray voltage cannot make one part of the pool area a few volts different from another. A landscaper who tears out the deck for pavers, a crew that trenches past the equipment pad, or an electrician who swaps a pump and leaves the bond lug empty can remove that protection without anything visibly changing. The pool still runs. The first sign can be a swimmer feeling a tingle at the ladder.

Safety first

• Anyone reports tingling, a shock, or a buzzing feeling in the pool or at a metal rail: get everyone out of the water and keep them out. Tell swimmers to get out without grabbing metal ladders or rails if they can use the steps. Do not jump in to help someone who is frozen in the water; shut the power first. Switch off every pool circuit at the panel or subpanel while standing on a dry surface, then call an electrician, and leave them off and the pool closed until the electrician has found and fixed the cause. If the tingle persists with all pool equipment off, the electrician may need the power utility to check for voltage coming from its side.
• A cut or exposed conductor that is not the bare bond wire (an insulated wire, a conduit, a cable to underwater lights): stop, keep people and tools away, and have the pool circuits switched off before anyone touches it. Call the electrician; the circuits stay off until the electrician has made the repair.
• A gas heater on the pad: a struck or kinked gas line means everyone moves away, no switches or engines, call 911 and the gas utility from a distance.

What the bond is, and what it is not

Equipotential bonding means connecting every conductive thing in and around the pool together so they all sit at the same voltage. If a fault or a stray current energizes one part, all of it rises together, and a person touching two parts at once has no difference to feel. NEC 680.26 (as adopted by your jurisdiction; it has been revised in recent editions, so check the one you are under) sets what has to be bonded.

It is not the equipment ground. The green wire in the pump's circuit is there to trip the breaker when something shorts. The bond is there to keep a pool area from becoming a set of different voltages. NEC 680.26 in substance does not require the bond to run back to the panel or a ground rod; it is a local grid around the water. An electrician cannot substitute one for the other, and neither can be left off because the other is present.

What gets bonded, in substance:

• The pool shell's reinforcing steel, for a concrete or gunite pool.
• The perimeter surface: the deck, pavers or even bare ground extending 3 feet horizontally from the inside walls of the pool. Where the deck has no bonded steel of its own, the common method is a ring of 8 AWG or larger solid bare copper buried under the surface, 18 to 24 inches from the inside walls of the pool and 4 to 6 inches below the subgrade, attached to the pool's steel or bonding grid at no fewer than four points spaced evenly around the pool.
• Metal parts of equipment: pump motors, heaters, metal filter housings, with an 8 AWG or larger solid copper conductor.
• Fixed metal within 5 feet of the inside walls of the pool horizontally, and within 12 feet above the water: ladders, handrails, metal fences, metal light poles, unless an exception in that section applies, such as a permanent barrier between the metal and the pool.
• The water itself, through a bonded fitting or plate in contact with it.

See related: Pool and Spa Electrical Bonding Reference.

The pad and the perimeter

 PLAN VIEW, POOL AREA BONDING

  +------------- 3 ft perimeter zone ----------+
  |  . . . . . copper ring 18-24 in . . . . .  |
  |  .  +------------------------------+    .  |
  |  .  |  POOL, inside walls          |    .  |
  |  .  |  steel shell (bonded)        |    .  |
  |  *  |  ladder anchors (bonded)     |    *  |
  |  .  +------------------------------+    .  |
  |  . . . . *. . . . . . . . . . . *. . . . . |
  +-------------------|------------------------+
     * = tie to shell |  bare 8 AWG copper,
       4 points min   |  buried, to the pad
                      v
       EQUIPMENT PAD  [PUMP]--[FILTER]--[HEATER]
                      lug       lug       lug
         bond wire runs lug to lug, bare,
         separate from the circuit's ground wire

At the pad the bond wire is easy to spot: a bare, solid copper wire, often with a green tint from oxidation, running into a lug on the pump motor, then on to the heater and any other metal equipment. Underground, it runs between the pool and the pad, often in no conduit and at no great depth.

Where landscapers break it

Replacing a concrete deck with pavers. The old deck may have carried the perimeter bond in its steel or in a ring poured with it. Breaking it out removes the bond. The new paver deck needs its own perimeter bonding installed before the base goes in, by an electrician, and in many jurisdictions it is inspected before anything covers it. Pavers laid directly on a fresh base with no ring leave the deck unbonded.

Trenching near the pad. A trench for an edge restraint, a drain line or low-voltage lighting between the pool and the equipment pad crosses the buried bond wire. A bare wire cut by a trencher does not spark and does not stop anything working; it simply disconnects the pad from the pool grid.

Burying or regrading at the pad. Piling soil or rock against the pad buries lugs and wires and holds water against the equipment. Keep grade falling away from the pad and leave the equipment accessible.

New metal near the water. A metal fence, a pergola with metal posts or a light pole within 5 feet of the water has to be bonded unless an exception applies. A landscaper installing it should raise that before the posts are set, not after.

Where electricians break it

Electricians know bonding, but the pool pad has its own traps:

• Pump motor replacement. The bond conductor comes off the old motor's lug and has to land on the new one. A new motor with an empty bond lug is the single most common way a pad loses its bond.
• Removing old equipment. An abandoned heater taken off the pad may have been the link in a lug-to-lug chain; pulling it can leave the pump on one side and the pool on the other.
• Splicing. The bond is solid copper; any splice is made with a listed connector suited for direct burial or wet locations, not a twist-on connector or tape.
• GFCI. Recent editions of NEC 680.21 require ground-fault protection for pool pump motors, as adopted, which affects a motor replacement on an older pad. Check what your jurisdiction is under.

Worked example: pavers around a 16 by 32 foot pool

A landscape crew is replacing a 3 foot wide concrete apron around a rectangular pool, 16 by 32 feet measured to the inside walls, with pavers, widening the deck to 5 feet. The customer also wants a new aluminum fence 4 feet from the water's edge on the long side.

What the demolition removes. The old apron was poured with welded wire mesh tied to the pool's bond. Once it is broken out, the pool area has no perimeter bond. The crew stops after demolition and before any base material goes down, and the customer's electrician is called in.

The ring the electrician installs. For this example the electrician runs a copper ring 21 inches (1.75 feet) out from the inside walls, inside the 18 to 24 inch window. Its path is a rectangle of (16 + 2 x 1.75) by (32 + 2 x 1.75) = 19.5 by 35.5 feet, so the ring is 2 x (19.5 + 35.5) = 110 feet of 8 AWG solid bare copper, set 4 to 6 inches below the subgrade. It ties to the pool's bond at four points, one every 110 / 4 = 27.5 feet around the ring.

How wide the bonding has to reach. The perimeter zone is 3 feet from the inside walls. The new deck runs 5 feet out, so the outer 2 feet of pavers lie outside the zone and need no added bonding; the ring at 21 inches covers the zone the code describes. The crew does not get to reason the other way: a narrower deck does not shrink the zone, because the zone includes bare ground too.

The fence. At 4 feet from the inside walls, the aluminum fence is inside 5 feet, so its posts have to be bonded unless an exception applies. The electrician bonds the posts on that run to the ring before the paver base buries the connection.

The trench by the pad. The crew also planned a 10 inch deep trench for a paver edge restraint and drain line passing between the pool and the equipment pad. The electrician traces the bond wire from the pump lug toward the pool and finds it crossing the trench route at about 8 inches deep. The crew hand-digs that crossing, exposes the wire, and lays the drain under it with the wire left intact and supported.

Inspection and close-up. The bonding is inspected before base and pavers cover it. Only then does the crew lay base, set pavers and backfill.

The tally. 110 feet of ring with four ties replaces the bond the demolition removed, the fence run is bonded, and the one bond wire crossing the trench is left whole. No change is visible on the finished deck, which is exactly why the sequence matters.

What changes the answer

Vinyl-liner and fiberglass pools. They have no steel shell, but the perimeter surface, the equipment and the water still need bonding. The ring ties to whatever the pool's bonding grid is. Do not assume "no steel, no bond."

Hot tubs and spas. Bonding rules apply to permanently installed spas too, with differences for listed self-contained units. Ask the spa installer or electrician before laying a deck around one.

Older pools. A pool built before perimeter bonding was required may never have had a ring. Replacing its deck is usually the moment an inspector expects one. Expect the electrician's scope to grow.

The words to use when you call

"We're removing the concrete apron around the pool at [address] and replacing it with pavers out to 5 feet. Demolition is done and the old mesh is gone, so the perimeter bond is out. Nothing is covered yet. We also have a trench planned between the pool and the equipment pad, and a new aluminum fence 4 feet from the water. Can you install and get the perimeter bonding inspected before we lay base?"

References

• National Electrical Code Article 680, Sections 680.21 and 680.26, as adopted by your jurisdiction; check the edition in force.
• The pool equipment manufacturer's installation manual for bonding lug locations.
• See related: Pool and Spa Electrical Bonding Reference
• See related: Describing a Problem in Another Trade's Own Words