Silicone vs Fiberglass vs PVC Sleeving: What Actually Differs
Three sleeves, three price points, three failure modes. The cheapest one melts first; the most flexible one does not seal. Match the sleeve to the threat, not the budget.
The three at a glance
| Property | Silicone rubber | Silicone-fiberglass | PVC |
|---|---|---|---|
| Max temp | ~180-200 °C | 200-260 °C | ~105 °C |
| Flexibility | excellent | good | good |
| Sealing | good | poor (sleeve) | fair |
| Cost | mid-high | mid | low |
Pick by threat
External radiant heat - fiberglass. Flex plus fluid resistance - silicone. Cost and dry indoor - PVC.
Sealing note
None of these sleeves seals a splice. For moisture, run adhesive-lined heat shrink over the sleeve ends.
Frequently asked questions
Highest temperature?
Silicone-fiberglass, up to about 260 °C.
Cheapest?
PVC, for low-temperature dry use.
How do I seal the joint?
Pair the sleeve with dual-wall adhesive heat shrink at the ends.