Pool Skimmer Leaking Water? Check This First
70% of suspected “skimmer leaks” are actually expansion joint failures around the skimmer. Here’s how to identify the real source and avoid costly misdiagnosis.
Most “skimmer problems” are actually failed expansion joints that can be fixed for 60% less cost than skimmer replacement.
4 Quick Tests: Skimmer Problem vs. Expansion Joint Failure
Do these simple tests before calling anyone. Results will tell you exactly what type of repair you need.
Water Level Test
Fill pool to normal level, mark water line, wait 24 hours
Water drops significantly (2+ inches)
Water drops slightly (½-1 inch), stops at skimmer bottom
Visual Inspection
Look around skimmer opening while pool is full
Cracks in skimmer body, loose fittings visible
Water seeping from deck/skimmer junction, mastic gaps visible
Dye Test
Squeeze food coloring near suspected leak areas
Dye gets sucked into skimmer cracks or fittings
Dye flows toward deck/skimmer gap, follows expansion joint
Deck Inspection
Check soil around pool for wet spots or settling
Minimal soil impact directly under skimmer
Soggy soil along deck perimeter, possible deck settling
Red Flags: This is an Expansion Joint Emergency
Water level stops dropping at skimmer bottom
Once water drops below expansion joint level, leak stops - classic expansion joint behavior
Mastic/caulk around skimmer is cracked or missing
Expansion joints protect against movement - failed joints allow water infiltration
Water stains on deck near skimmer
Water escaping through failed joints surfaces on deck, leaving mineral stains
Deck settling or cracks near skimmer area
Escaping water saturates soil, causing foundation movement and structural damage
When It Actually IS Your Skimmer (Less Common)
Visible cracks in skimmer body
Physical damage to skimmer housing allows direct water escape
Loose plumbing connections inside skimmer
Pipe fittings have worked loose, allowing water to bypass system
Water continues dropping below skimmer level
Leak source is lower in system - main drain, returns, or underground plumbing
The Cost of Misdiagnosis: Why This Matters
📋 What You See
Pool loses 2 inches overnight
❌ Wrong Assumption
Skimmer must be broken
Skimmer replacement: $800-2,000
✅ Likely Reality
Expansion joint failure allows rapid water escape when pool is full
Mastic repair: $750-1,200
📋 What You See
Water stops at skimmer level
❌ Wrong Assumption
Skimmer is working - leak must be elsewhere
Searching for non-existent leaks: $500-1,500
✅ Likely Reality
This is exactly what expansion joint leaks do - stop when water drops below joint
Joint repair: $750-1,200
📋 What You See
Wet soil only near skimmer
❌ Wrong Assumption
Skimmer plumbing leak underground
Excavation and plumbing: $2,000-5,000
✅ Likely Reality
Failed expansion joint allows water to escape and pool at lowest point (skimmer area)
Surface joint repair: $750-1,200
💡 Average Savings: $1,300-3,800 by Identifying the Real Problem
Most pool owners waste money fixing the wrong problem. Proper diagnosis saves thousands and solves the leak permanently.
Emergency Response: What to Do Right Now
Stop further water loss
Do immediatelyLower pool water below suspected leak level to prevent ongoing damage
Document the leak pattern
Within first hourTake photos of water stains, mastic condition, and surrounding deck area
Check for structural damage
Same day assessmentLook for deck settling, cracks, or soil erosion around leak area
Contact expansion joint specialist
Within 24 hours for structural leaksSkip general pool repair - go directly to mastic/joint specialists for fastest resolution
Need Professional Assessment?
Our Skimmer Leak Specialists Provide:
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Understand the Urgency →Pool Mastic Replacement
Professional expansion joint repair - the permanent solution for most “skimmer leaks.”
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