Pool Light Leak Repair

What Is Pool Light Leak Repair?

Pool light leak repair is the work of fixing leaks at the pool light niche — the recessed housing in the pool wall that holds the underwater light fixture. Pool lights themselves don't typically leak in a way that loses water — the light fixture is sealed. But the niche behind it has a conduit running back to a junction box or breaker, and that conduit is one of the most common (and most overlooked) sources of slow pool water loss.

Light niche leaks are sneaky. The water doesn't go into your pool deck or yard — it goes through the conduit, traveling potentially 20 feet or more behind the pool wall, into the junction box, sometimes into your house wall or foundation. By the time most homeowners notice, real damage may already be done.

How Pool Lights Leak

The leak is almost never the light itself. The leak is at the seal between the light, the niche, and the conduit.

Conduit seal failure. The conduit (typically a metal or PVC pipe) carries the wiring from the niche back to the junction box. The connection between the conduit and the niche is sealed during construction. Over decades, that seal degrades — or it was poor from day one — and water enters the conduit.

Niche cracks or separations. The niche itself can crack from ground movement, freeze damage, or shell stress. Cracks let water out around the niche body.

Niche gasket failure. The light fixture seals to the niche with a gasket. A bad gasket can let water into the back of the niche when the light is removed, but this is rarely the source of a continuous leak (since the fixture being seated re-seals it).

Junction box water entry. Once water enters the conduit at the niche, it travels uphill or downhill (depending on the layout) to the junction box on the deck or in the wall. From there it can drain into walls, soil, or the ground.

Signs of a Pool Light Leak

Light leaks are notoriously hard to detect from inside the pool because the niche stays full of water either way. Signs to watch for:

• Slow, persistent pool water loss with no visible source elsewhere
• Water in the junction box on the deck (open it carefully — it may be live)
• Wet or efflorescing wall behind the pool, especially on the side closest to the light
• Tripping GFCI on the pool light circuit (wet wiring trips the GFCI)
• Corrosion on the light fixture wiring
• Damp insulation in the wall behind the pool's light fixtures

If you've eliminated other leak sources and your pool is still losing water — light niches should be tested.

Our Pool Light Leak Repair Process

Step 1 — Verify the leak source. We check the junction box for water, dye-test around the niche, and look for evidence of conduit-side water travel.

Step 2 — Coordinate electrical safety. Pool lights are 120V or 12V circuits. We ensure power is off and verify the circuit before any work.

Step 3 — Reseal the conduit at the niche. The most common repair: pull the wiring back, remove old sealant, and re-seal the conduit-to-niche penetration with proper underwater-rated sealant.

Step 4 — Test the repair. We monitor the junction box and the pool's water loss after the repair to confirm the leak is resolved.

Repair Methods

• Conduit seal at niche: Underwater-rated sealant repack
• Niche hairline crack: Epoxy injection
• Niche structural crack: Niche replacement (significant scope)
• Junction box water: Drain box, repair conduit seal upstream, re-seal
• Failed light gasket: Replace gasket (during fixture service)
• Severe niche damage: Full niche removal and replacement

Why Pool Light Leaks Need Attention

Beyond the water loss, light niche leaks have safety and structural consequences:

• Electrical risk. Wet pool light wiring can trip GFCIs, damage fixtures, and in rare cases create shock hazards if grounding is compromised.
• Wall and foundation damage. Conduit traveling back to the house can deliver water into the wall cavity, causing rot, mold, and structural damage.
• Pool deck erosion. Junction boxes that fill with water can spill onto deck soil and erode the area around the pool.
• Ongoing water loss. Even a slow conduit leak running 24/7 adds up to thousands of gallons over a year.

Coordinating with Electricians

Most pool light leak repairs don't require electrical work — they're sealing problems, not wiring problems. But if the wiring itself has been damaged or the GFCI is failing, we coordinate with licensed electricians for any electrical-side work. We don't do work outside our license, and we don't ask you to hire a separate contractor unless the job genuinely requires it.

Cost & Timeline

Most light niche leak repairs are completed in 1 to 3 hours and are same-day. Niche replacement is a more involved repair, sometimes requiring partial drainage, but is rarely necessary.

Pool Light Leak Repair FAQ

My pool light still works — can it still be leaking?

Yes. The light fixture and the niche are different. The fixture can be perfectly functional while the conduit seal behind it is failing.

How do you find a pool light leak?

Dye testing at the niche, checking the junction box for water, and process of elimination after testing other potential leak sources.

Will the pool need to be drained?

Usually not. Most niche seal repairs can be done from inside the niche with the pool full or with the water level slightly lowered.

Can my pool light cause electrical shock if it's leaking?

Modern pool lighting on a properly grounded GFCI circuit is designed to fail safe — the GFCI trips before any shock hazard reaches the water. But a leak with a failed GFCI is a real concern. If your pool light circuit is tripping GFCI, don't reset it without checking the source.

Why didn't my home inspector catch this?

Most home inspectors don't open junction boxes or test pool lights beyond a basic on/off check. Light niche leaks are a specialized failure mode that requires pool-specific knowledge to identify.

Can old pool lights be retrofitted to LED at the same time as the repair?

Yes — if you're already opening the niche for a repair, it's a logical time to upgrade to LED. We can coordinate the upgrade with the repair.

Address Light Niche Leaks Early

If you suspect a light niche leak — or if you've ruled out other sources and your pool is still dropping — call (508) 641-4529 for a free quote, or request a callback.