Silicone Inside or Outside the Shower Frame?
Outside. On most shower enclosures and bath screens, silicone goes along the outside of the wall profiles and the outside of the bottom frame, not the inside. Any water that gets past the glass then runs back into the tray or bath instead of being trapped behind a bead of silicone and pushed out under the frame. The joint between the tray and the wall is the exception: seal that before the enclosure goes in. Always follow the enclosure maker’s fitting instructions where they differ.
Why outside, not inside
Water gets inside every frame: through the joints, the drain gaps and the space behind the glass. Frames are usually designed to let it drain back into the shower. Silicone on the inside blocks that path, so water collects in the frame and finds its own way out, usually under the outside edge and onto the floor. Silicone on the outside stops water leaving the enclosure while letting the inside drain.
Where silicone goes and where it doesn’t
| Joint | Silicone? | Which side |
|---|---|---|
| Shower tray to wall (tiles) | Yes, before fitting the enclosure | Full length, continuous |
| Wall profile to wall | Yes | Outside only |
| Bottom frame to tray | Yes | Outside only; leave drain slots and weep holes clear |
| Fixed panel glass to wall (frameless, no profile) | Usually yes, or a glass-to-wall seal | Outside, or as the maker states |
| Hinged or sliding door edges | No | These move: use a clip-on seal |
| Door bottom | No | Use a bottom seal or sweep |
| Between two panels that meet | Fixed: as the maker states. Moving: no | Use a glass-to-glass or magnetic seal |
Silicone for fixed joints, seals for moving ones
Silicone bonds two surfaces that never move. On a door edge it tears the first time the door opens. Moving edges need a clip-on seal: a bottom seal under the door, a hinge-side seal at the wall, a magnetic or soft seal on the closing edge. If your enclosure leaks at a moving edge, see why shower screens leak at the hinge.
How to reseal without trapping water
- Cut out the old silicone with a sharp blade or plastic remover; don’t scratch the tray or glass.
- Clean the joint with isopropyl alcohol and let it dry fully (a day if possible).
- Run the shower tray-to-wall joint first if it is the problem: tape both sides, apply a continuous bead of sanitary silicone, tool it, remove the tape.
- Seal the frame on the outside only, keeping drain slots at the bottom of the frame open.
- Leave it to cure for at least 24 hours (or as the tube says) before using the shower.
Use a sanitary silicone with an anti-mould additive. Acetoxy (vinegar-smelling) silicone is commonly used on ceramic and glass; check the tray maker’s advice for acrylic or stone-resin trays.
Trade buyers: GoldRays makes the seals for the moving edges: bottom, hinge-side, magnetic and glass-to-glass profiles for 4 to 15 mm glass. Request samples.
Frequently asked questions
Should I silicone the inside of my shower screen?
No, in most cases. Silicone on the inside traps water in the frame. Seal the outside, and use clip-on seals on any edge that moves.
My new enclosure leaks even though I siliconed it. Why?
Often the silicone is on the inside and water inside the frame has nowhere to go, or the drain slots at the bottom of the frame are blocked. Check also the tray-to-wall joint and the seals on the door.
Can I use silicone instead of a shower door seal?
No. A door edge moves every time the door opens, and silicone tears. Use a seal made for your glass thickness and gap.
Do frameless showers need silicone?
Fixed panels usually need silicone or a glass-to-wall seal where they meet the wall and tray, on the outside. The door itself relies on seals.
About the author
GoldRays technical team
The GoldRays technical team writes these guides at the GoldRays factory in Foshan, China, where clear PVC and polycarbonate shower door seals have been made since 2001. The team works with more than 40 production lines and more than 3,200 moulds for 4 to 15 mm glass, and answers trade questions about fit, materials and testing.
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