PVC or Hypalon? How to Tell What Your Inflatable Dinghy is Made Of
If you’ve got an inflatable dinghy and you’re not quite sure what it’s made from—PVC or Hypalon (CSM)—you’re not alone. This question comes up all the time, especially when buying a second-hand boat or trying to figure out what glue or patch kit to use for a repair.
The problem? The two materials often look and feel pretty similar, especially if the boat is a few years old. But there are a few telltale signs to help you figure it out.
Why It Matters
Before we jump into how to tell the difference, here’s why it’s worth knowing:
- Repairs: Different materials need different adhesives and patch kits.
- Care and maintenance: Hypalon handles UV and salt better; PVC needs a bit more babying.
- Resale and value: Hypalon dinghies typically hold value longer.
- Storage: PVC dinghies should ideally be stored out of direct sunlight; Hypalon is more forgiving.
1. Look at the Seams
One of the easiest ways to spot the difference is by checking how the seams are joined.
- PVC:
Seams are usually heat-welded or high-frequency welded. They’ll appear flat, smooth, and almost melted together. No glue residue. - Hypalon:
Seams are hand-glued. You’ll often see a bit of glue or a fabric overlap at the joints. The seam might be slightly raised or have a visible edge.
Quick tip: If it looks stitched or overly ‘manual’, it’s probably Hypalon.
2. Feel the Texture
Each material has a different look and feel, even if the difference is subtle.
- PVC:
Usually smoother, shinier, and slightly plasticky to the touch. It might feel stiffer in cooler weather, and more flexible when it’s warm. - Hypalon:
Has a more matte or textured rubbery finish. It feels more like soft rubber and tends to stay fairly consistent regardless of temperature.
Pro move: Tap it with your fingernail. PVC sounds a bit sharper or ‘plasticky’, while Hypalon sounds duller.
3. Check the Inside of a Valve or Underside of a Patch
If your dinghy has any worn patches, exposed fabric, or a lifting valve ring, that can be your best clue.
- PVC:
The fabric under the surface will usually be white or grey, with a plastic-like feel. - Hypalon:
The backing will typically be black or dark grey, and feel more like cloth or canvas.
You can also look under a rubbing strake or grab handle if the glue is lifting a bit—just don’t peel anything up unless you’re already repairing it.
4. Do the Acetone Test (Carefully)
If you’re still not sure and you’re okay doing a quick spot test, you can use acetone or nail polish remover on an inconspicuous area.
- PVC:
Acetone will soften or smear the surface slightly. You might see a bit of color come off onto the cloth. - Hypalon:
Acetone won’t affect it much at all. It’s chemically resistant.
Warning: Only do this in a hidden spot, and don’t go overboard—you don’t want to damage a good dinghy just to ID it.
5. Manufacturer Plate or Branding
Sometimes the simplest way is just to check the spec plate or logo.
- Many manufacturers will list the fabric type on the serial plate or tag.
- If you have the brand and model, a quick online search often reveals the material used.
Example: Zodiac, Highfield, and Achilles often clearly state what their boats are made from. Some brands even offer the same model in both materials.
Final Thoughts
Figuring out whether your dinghy is PVC or Hypalon isn’t always obvious at first glance, but with a bit of detective work, you can usually tell. When in doubt:
- Check the seams
- Feel the texture
- Look underneath or inside
- Use a little acetone (cautiously)
- Search the make/model if you can
Once you know what you’ve got, you’ll be able to care for it better, patch it properly, and maybe even boost its resale value.