PVC vs Polycarbonate vs Silicone Shower Seals
Most clear shower door seals are made of flexible PVC, which is typically clear, flexible and inexpensive. Polycarbonate is usually used where a seal needs to be rigid and very clear, such as glass-to-glass connectors and some hinge profiles. Silicone and TPE are softer and typically stay flexible in the cold, but are usually translucent rather than glass-clear. How long a seal lasts depends less on the material name than on the additives in the compound, especially UV stabilisers and anti-mould agents.
Comparison
This is general guidance on how the material families typically behave. Individual compounds vary, so ask for test data on the actual seal.
| Flexible PVC | Polycarbonate (PC) | Silicone | TPE | |
|---|---|---|---|---|
| Clarity | Typically clear | Typically very clear, glass-like | Translucent to clear | Usually translucent |
| Flexibility | Flexible fins and bubbles | Rigid | Very soft | Soft to medium |
| Typical positions | Bottom sweeps, side seals, magnetic housings | Glass-to-glass connectors, rigid hinge and closing profiles | Soft bottom seals, self-adhesive strips | Bottom and side seals |
| Yellowing risk | Depends on UV stabilisers and plasticiser | Depends on UV stabilisers | Typically low | Typically low to medium |
| Mould risk | Depends on antimicrobial additives | Typically low (rigid, smooth) | Can stain if not treated | Depends on additives |
| Relative cost | Typically low | Typically medium | Typically higher | Typically medium |
| Co-extrusion | Common (rigid PVC grip + soft fin) | Often combined with soft PVC fins | Less common | Often combined with PP |
Flexible PVC
The workhorse of shower seals. A grip channel for the glass and a soft fin or bubble can be extruded together, often in two hardnesses. Quality typically varies more than with any other material: the type and amount of plasticiser decides how long the fin stays soft, and UV stabilisers decide whether it yellows. Ask for UV-ageing data (ASTM G155 xenon-arc) on the actual compound.
Polycarbonate
Rigid and typically the clearest option, so it suits joints where the seal is on show: glass-to-glass connectors at 180°, 90° or 135°, and slim closing profiles on frameless doors. It needs UV stabilisation like any clear plastic. Because it’s rigid, it’s usually combined with a soft PVC fin where a seal must flex.
Silicone
Very soft and typically flexible over a wide temperature range, and resistant to yellowing. It’s used for soft bottom seals and self-adhesive strips. It is usually less glass-clear than PVC or polycarbonate, typically more expensive, and can attract dirt unless the surface is treated.
TPE (thermoplastic elastomer)
A rubber-like plastic that stays flexible without plasticisers, so it doesn’t harden through plasticiser loss. It’s typically less clear than PVC and is more often used in translucent or coloured seals.
What GoldRays makes
GoldRays makes clear PVC and polycarbonate seals. In SGS testing, SuperClear™ samples showed no yellowing after 300 hours of ASTM G155 xenon-arc exposure and rated Grade 0 (no growth) in ASTM G21 and ISO 846 mould tests. See the test results.
Trade buyers: request samples to compare clear PVC and polycarbonate profiles on your glass.
Frequently asked questions
What is the best material for a shower door seal?
For clear seals on frameless glass, typically a UV-stabilised PVC or polycarbonate with antimicrobial additives. For soft seals where clarity matters less, silicone or TPE. Ask for test data rather than relying on the material name.
Do silicone shower seals last longer than PVC?
Silicone typically resists yellowing and stays flexible, but a well-formulated, UV-stabilised PVC can also stay clear for a long time. Compound quality usually matters more than the material family.
Why did my PVC seal go hard?
Plasticisers that keep PVC flexible can migrate out over time, especially with heat and strong cleaners. Higher-quality plasticisers and gentler cleaning typically slow this down.
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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