A leak at a panel-to-panel corner is a joint problem rather than a bottom-edge problem. Water reaches the corner along the overlap between the two panels and passes through the joint where they meet, so replacing a sweep or a bottom seal leaves the path it is using untouched. The fix belongs at the joint itself.
This is the reason corner leaks are so often treated twice without success. The water arrives at the floor, the bottom edge looks like the culprit, and the part nearest the evidence is replaced - while the joint the water actually travelled through is never examined.
The Path Water Takes at a Panel Joint
On a sliding enclosure the panels pass each other rather than meeting at a closed edge, and the place they cross is a permanent joint in the enclosure. Water that lands on the glass or is thrown against the overlap edge finds its way into that joint, then travels down it - partly under gravity, partly by being drawn into the narrow gap - and arrives at the bottom of the enclosure inside the line of the sweep.
Three conditions make the path more likely. A joint whose profile is missing, compressed or trimmed short has an opening where the panels cross. A joint that sits in the spray path is loaded with more water than one that does not. And a joint between panels at different heights, which happens when the two panels are adjusted differently, is not a straight gap but a changing one, and a profile made for a straight joint will not close it.
Water reaches a panel-to-panel corner along the joint itself, so repairing the bottom edge leaves the path it uses untouched. Confirming the path before touching any part is what stops the same leak being "fixed" a second time.
Why Bottom-Edge Repairs Do Not Resolve a Joint Leak
The bottom edge and the panel joint look like the same fault because the water ends up in the same place. They are not the same fault, and the tests that separate them are simple.
| What you see | What it suggests | What it rules out |
|---|---|---|
| Water appears along a length of the bottom edge | The sweep is not making contact along its run | A single local defect |
| Water appears at one point under the joint | The joint is passing water | The sweep as the primary cause |
| The leak follows the spray direction | Aimed water is reaching the joint | A worn part |
| The leak only appears when the panels are in one position | The joint gap changes with position | A profile that needs replacing |
Where the water arrives at one point beneath the joint, the useful next check is the joint itself: is the profile present along the whole overlap, does it still make contact, and is it compressed at one end and open at the other? A joint that is intact and a bottom edge that is intact point at the direction of the water rather than at a part, which is a different repair again.
The order to seal a joint
Sealing a joint is a sequence, and doing the steps out of order is what leaves a joint that leaks again.
- Clean and dry the joint. Profiles and sealants do not bond to a wet or soapy surface, and a joint that is dried only at the visible edge will still be wet inside.
- Put the door in its final position. The panels' heights and the overlap gap should be set before anything is sealed, because sealing fixes the geometry in place.
- Replace the moving profile if it is the part at fault. A joint that is closed by a flexible profile is closed by that profile, not by sealant.
- Seal only the static parts of the joint. A sealant belongs where two surfaces meet and stay still; applying it to a part that has to move takes the movement out of the profile and usually causes the next leak.
- Test with the spray before using the shower normally. Run the shower at the angle it is normally used, and check the joint rather than the floor.
The order matters because each step depends on the one before it: a joint sealed before the door was adjusted has to be reopened once the door moves, and a profile replaced before the joint was cleaned will not seat properly.
Joint Faults That Require a Replacement Part
Three joint faults are not resolved by adjustment or cleaning, and all three are visible before anything is ordered.
- A profile that is missing or trimmed short at the overlap, so the joint is open at one end.
- A profile that has hardened or deformed, so it no longer takes the shape of the gap it is closing.
- A changed geometry - panels adjusted to different heights, or a joint that is no longer straight - where the profile was made for the original arrangement.
Replacing a joint profile means matching the profile to the joint rather than to the door's name, and the measurements that decide it are the gap the profile closes and the way it is held. The replacement seal measurement guide covers what to record, the water containment guide explains how the parts of the enclosure work together, and the bottom-leak guide covers the case where the diagnosis really does point at the bottom edge.
Bring the door to its final position, close the joint with the profile that belongs there, seal only what does not move, and test with the spray before the shower returns to normal use. Doing those four in that order is what stops the same leak being repaired twice.