Shower Door Still Leaks After a New Seal
Quick answer
A new seal that still leaks almost always means the water is taking a path the new part never covered: runoff off the bottom corner (needs a drip rail, not a taller wipe), a sagged door sealing one end only, spray aimed straight at the door line, a curb sloping the wrong way, or — on framed doors — clogged weep holes. Diagnose in that order before buying anything else.
Last updated: · Data reviewed: · Source: Prime-Line product specifications
First: watch one full shower cycle
Run the shower for two minutes and watch the door from the bathroom side with a flashlight. Where the water appears tells you which of five failure paths you have — and every path has a different fix. Guessing here is how people end up with three seals stacked on one door.
Symptom → next check
| What you observe | What it means | Fix |
|---|---|---|
| Drip forms at the bottom outside corner | Runoff sheets down the glass face and exits at the corner | Add a drip rail or a sweep-with-rail combo |
| Wet at the handle end only | Door sagged; gap uneven so the wipe seals one end | Re-square the door on its hinges, then re-measure |
| Water pulses out when spray hits the door | Direct spray or bounce-back splash overpowering the fin | Re-aim the head; use a dual-fin splash sweep |
| Slow puddle at the door line, sweep looks perfect | Curb flat or sloped toward the bathroom | Surface-mounted threshold / water dam on the curb |
| Framed door: seepage under the frame itself | Weep holes clogged; corner joints leaking | Clear weeps with a pick; reseal frame corners |
| Vertical stripe of spray at an edge | Side gap uncovered — wrong seal location replaced | Fit a side, bulb, or magnetic seal on that edge |
The 10-minute diagnostic, in order
- Dry everything. Towel the floor, curb, and glass so new water is unambiguous. Lay a paper towel line along the bathroom side of the door.
- Check overlap. With the door closed, the wipe should press the threshold with 1/8–1/4 in of flex. See daylight? The wipe is too short for the gap — verify your gap numbers at both ends.
- Check the corners. Run water down the inside glass face only (handheld or a cup). Corner drip now = runoff problem = drip rail territory.
- Check alignment. Measure the gap at hinge and handle ends. A difference over 1/8 in is hinge sag; adjust before judging the seal.
- Check spray geometry. Note whether the leak only happens when the showerhead points toward the door. Re-aim toward the control wall and retest.
- Check the curb with a level. The curb top should pitch slightly INTO the shower. A flat or outward pitch sends water to the bathroom no matter the seal — add a threshold strip.
- Framed doors: check the weeps. Find the small slots on the shower side of the bottom rail; clear them with a zip tie. Water trapped in the rail exits at corroded corners otherwise.
Dead ends to skip
- Stacking a second sweep over the first — the joint between them leaks.
- Caulking a swinging door edge shut in frustration.
- Buying an ever-taller wipe while a body jet fires at the door line.
- Blaming plumbing and opening a wall before checking runoff and curb slope.
- Sealing frame weep holes with silicone — they are drains, not defects.
Frequently asked questions
Why does my brand-new sweep leak at one corner?
Almost always face runoff: a film of water travels down the outside of the glass and exits at the lowest corner, bypassing the wipe entirely. A drip rail on the outer face redirects it back into the shower.
Can a shower door ever be 100% watertight?
Frameless doors are designed to be water-resistant, not submarine-tight — tiny weeping at extremes is normal. The goal is no water reaching the bathroom floor under normal use, which the fixes above achieve.
How do I know if the leak is the curb, not the door?
Lay a level on the curb: the top should slope slightly into the shower. Pour a cup of water on the curb with the door open — if it runs toward the bathroom, no seal will save you; add a threshold or have the curb corrected.
The old seal never leaked; the identical new one does. Why?
Usually the door moved between seals — hinge creep widened or tilted the gap — or the “identical” part has a shorter wipe than the original had when new. Measure the gap at both ends and compare against the new wipe height.