Replace Yellowed Shower Seals (Leak-Free Finish)
UK homeowner’s guide. Yellowed or cracked shower door seals cause leaks, squeaks and a tired look. This step-by-step shows you how to choose the correct profiles, measure precisely, remove residue without scratching, and fit new seals for a clean, watertight finish. If you’re comparing glass strength types while upgrading, skim our primer on tempered glass first.
Overview
Most frameless shower doors use push-on or clip-on PVC/TPR seals that grip the glass edge. You’ll typically replace a bottom sweep (to deflect water into the tray) and 1–2 side seals (hinge and latch/meeting edges). Performance depends on a snug grip for your glass thickness (often 8–10 mm), a true “kiss” between the sweep and threshold, and clean, square meeting lines at the latch side.
Skill: Easy–moderate · Time: 45–90 min · Typical cost: £15–£40 per door (seals)
Seal Profiles (Quick Chooser)
| Position | Profile | What it does |
|---|---|---|
| Bottom edge | Sweep with single or twin fins | Deflects water back into tray; sets “kiss” on threshold |
| Latch/meeting edge | Magnetic pair or H/T profile | Closes gap; gentle magnetic draw for tight seal |
| Hinge side | Straight push-fit | Stops spray near hinge hardware |
| Door–fixed panel joint | U-channel clip with soft fin | Bridges door to side panel on two-panel enclosures |
Match by thickness: The “U” grip must suit your glass (6/8/10 mm). Too tight = stress on glass; too loose = slips and leaks.
Tools & Materials
- Fine saw or heavy scissors · Ruler · Masking tape · Pencil · Spirit level
- Isopropyl alcohol (IPA) & lint-free cloths · Plastic scraper (old store card works)
- Replacement seals: bottom sweep + side seal(s) to your thickness
- Optional: Neutral-cure sanitary silicone (only for channels/frames as per manufacturer)
Measure & Compatibility Checks
- Glass thickness: Check manual or measure with calipers (common: 8–10 mm).
- Bottom gap: Close the door and measure to the tray/threshold. Choose a sweep whose fin lightly touches without drag.
- Latch gap: Measure the meeting gap; for magnetic pairs, ensure profile depth suits your gap so magnets meet flush.
- Floor fall: If the floor falls outwards, pick a sweep with a longer or angled fin, or you’ll still get drips.
Remove Old Seals & Residue
- Open the door. Starting at one end, pull the old seal straight off the glass edge. If brittle, remove in short sections.
- Remove adhesive dots/silicone smears with a plastic scraper. Avoid metal blades on glass edges.
- Wipe the glass edge with IPA until squeaky-clean and dry. Inspect hardware gaskets; replace any that are crushed or missing.
Fit New Seals (Side & Bottom)
General tip: Warm the seals indoors for 10–15 minutes so they’re pliable and seat evenly.
Side seals (hinge/latch)
- Cut the seal 1–2 mm long. Test-fit; trim flush after final seating.
- Push the rigid “U” squarely onto the glass so the soft fin just touches the frame or fixed panel (no buckling).
- For magnetic pairs, check polarity and height; the magnets should meet neatly down the full length with a gentle draw.
Bottom sweep
- Close the door and measure the bottom edge. Cut the sweep square; de-burr the cut end.
- Push the sweep fully onto the glass. The fin should kiss the threshold — smooth contact, no scraping.
- Test the swing: open/close 5–10 times. If it drags, trim 1–2 mm or swap to a sweep with a shallower/angled fin.
Leak Test & Fine Tuning
- Run water for 2–3 minutes. Check hinge side, latch line and under the door.
- Latch drips: Nudge the side seal outward 1–2 mm so the fin sits square.
- Under-door drips: Raise the sweep slightly or change to a longer/angled fin if the floor falls outward.
Common Mistakes (and Fixes)
- Wrong thickness: Too-tight “U” grips stress glass; too-loose grips slip. Order for your exact thickness.
- Fin too long: Drag twists the door and wears quickly. Trim in 1–2 mm steps.
- Magnet polarity reversed: If strips repel, flip one end-for-end and re-fit.
- Sealing both sides of a channel: Traps water. Seal only as the hardware instructions specify.
Aftercare & Maintenance
- Daily: Quick squeegee to prevent mineral lines.
- Weekly: pH-neutral cleaner on seals and glass; avoid abrasives.
- 6–12 months: Replace sweeps that stiffen/yellow; check magnet draw and hinge alignment quarterly.
FAQs
Do I need silicone to hold seals on?
No. Most are push/clip-fit. Use silicone only for channels/frames as directed.
Will new seals fix a badly sloped floor?
They help, but if water falls outward you may need an angled fin and/or to correct the threshold.
How do I confirm glass thickness?
Check the manual or measure with calipers. Common sizes are 8–10 mm for frameless doors.
Is laminated better than toughened here?
For shower doors, toughened is standard; laminated is used elsewhere for security/acoustics. See tempered glass for strength basics.
Still seeing drips? The issue may be alignment, hinge set-out, or tray fall — ask Glass Helper for a quick check.