If you are putting in a pool this summer in Burlington, Oakville, Ancaster, or anywhere in the Golden Horseshoe (or a cottage pool up in Huntsville) the electrical trade is going to show up at the end of the project and set the schedule for everything after. The shell goes in, the plumbing goes in, the equipment pad goes in, and then we arrive to bond, to wire, and to walk the ESA inspector through the install. Until we sign off, the pool is not legally fillable. Here is what new pool owners should understand about that sequence, and where it can go sideways. For the deeper code conversation, see our existing pool and hot tub bonding post.
Why the electrical trade is last and why that matters
The pool electrical scope cannot be roughed in before the shell, the bonding grid, and the equipment-pad locations are committed. The pool contractor sets the deck height, the perimeter steel, the equipment pad footprint, the heater location, and the underwater light niche locations — and our work follows those commitments. If a pool installer is asking us to "pre-wire" before any of that is set, the wiring will end up in the wrong place and have to be redone.
The practical implication: the electrical scope is on the critical path for pool commissioning. Pool gets built, pool gets filled, pool gets opened — except none of that happens until the ESA inspector signs off the electrical. So the date you can swim is the date the electrical permit closes, not the date the shotcrete cures.
The bonding grid: the scope nobody quotes high enough
The OESC section 68 requirements for pool bonding are specific, extensive, and the single biggest place where uninformed installs get it wrong. We have written the full code conversation in our pool electrical bonding post; the short version for new owners:
- The perimeter steel in the deck around the pool (typically rebar embedded in the concrete deck) has to be tied into the bonding grid with #6 AWG solid copper at multiple connection points around the perimeter.
- Every piece of metal within 3 metres of the pool (handrails, ladders, dive boards, light niches, slide hardware, perimeter fence steel within reach) has to be bonded to the grid.
- All pump and motor enclosures, the heater, and any in-water lights are bonded back to the grid.
- The equipotential bonding plane in the deck (copper conductor or wire mesh) must extend a minimum distance from the pool edge.
- The bonding network ties to the system grounding electrode at the cottage or house main panel.
The reason all of this matters is the same as for waterfront docks. A person in the water between two metal objects at different potential becomes the path. Bonding eliminates the potential difference. The inspector will physically verify the connections, the conductor sizing, and the topology. If any of it is wrong, the pool is not getting energized.
The equipment-pad scope
The equipment pad (typically a concrete pad near the pool with the pump, filter, heater, and chemical-feed equipment) is where most of the electrical labour lives.
- Pump circuit. Dedicated 240V or 120V circuit depending on the pump rating. Variable-speed pumps (now nearly universal for new installs because of energy efficiency requirements) want 240V and proper start/stop wiring.
- Heater circuit. Electric heat pump pool heaters draw 30-50A continuous on a 240V circuit and need a dedicated breaker. Gas heaters need a 120V control circuit and an interlock. Either way, dedicated.
- Lighting low-voltage transformer. Underwater pool lights are universally low-voltage now — typically 12V LED in dedicated niche fixtures. The transformer mounts on or near the equipment pad with a dedicated 120V feed.
- Chemical-feed circuits. Chlorinator, salt cell, automatic chlorinator — small loads each, but each one needs to be on the right kind of circuit with the right GFCI protection.
- Equipment-pad GFCI tree. Convenience receptacle near the equipment pad has to be GFCI-protected per OESC. Common landing spot for the pump cord on installs that did not hardwire it.
- Disconnect within sight of every motor. Pump, heater, blower (if you have a spa coupled to the pool) — each has a disconnect within sight that an inspector can verify.
The panel question
Pools add real load. A 50A heater plus a 15A pump plus 5A of accessory loads adds 70A of continuous-rated demand. On a 100A service in a 1970s Hamilton bungalow with central AC and electric range already drawing, the load calc usually says the existing service is past limit.
The answer at the design stage is to run a real load calc on the existing house before the pool contractor pours the deck. If the service has capacity, the pool wiring lands at the existing main panel. If not, the conversation opens to a service upgrade or a sub-panel at the equipment pad fed by an appropriately-sized feeder. Catching this at design saves weeks of schedule slip later.
The trenching question
Conduit from the panel out to the equipment pad gets buried. Trench depth, conduit type, and routing all matter:
- Direct-burial PVC at minimum 60 cm depth for most runs, more if the run crosses a driveway or vehicle path
- NMWU direct-burial conductor inside the conduit, with proper bushings at every conduit end
- Conduit pulled with a fish tape during install, not stuffed afterward
- Pull strings left in for future low-voltage additions
The trench goes in once. If the pool contractor is excavating for the pool shell anyway, that is the moment to lay the conduit too — coordinated with the pool builder so the trench is open when we need it. We work that out at the pre-construction meeting.
The ESA inspection sequence
The ESA permit on a pool install typically gets two inspections — a bonding-grid rough-in inspection before the deck is poured, and a final inspection after all equipment is installed and energized. The bonding-grid inspection is the make-or-break one: if it fails, the deck cannot pour. If the inspector cannot see a bonding connection because the deck already covered it, the connection has to be exposed.
The sequence we run on every pool install:
- Bonding grid laid down, with photos at every connection
- ESA inspector walks the grid before the deck pours, signs off the rough-in
- Pool contractor pours the deck
- Equipment pad gets wired
- Underwater lights and niche connections finished
- Energization, ESA final inspection
- Certificate of Inspection issued
What new pool owners should ask
- Who is pulling the ESA permit? If the pool contractor is sub-ing the electrical to an unlicensed installer, walk away. The permit has to be in the name of an ESA Licensed Electrical Contractor.
- When is the bonding-grid inspection? Get a date pencilled in early — it is the gate to pouring the deck.
- Does the load calc say my panel handles it? Ask to see the math.
- Is there a separate quote for the electrical? Bundled "we handle everything" quotes from pool contractors that include the electrical have a track record of cutting corners on the bonding scope. A separate, line-item electrical quote means the work is being priced on its own merits.
- Who handles the heater coordination? If you are installing a gas heater, there is a gas fitter involved and the gas-fitter scope coordinates with ours.
When to call us
If you are putting in a pool this summer in Hamilton, Burlington, Waterdown, Ancaster, Dundas, Stoney Creek, Oakville, or a cottage pool in Muskoka, get us into the conversation at the design stage. We do the load calc, identify whether a service upgrade is needed, scope the bonding and equipment-pad work, and coordinate with the pool contractor on trenching and inspection timing. Request a pool electrical quote.