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Zodiac pvc dinghy on a beach after having a repair

Is My Boat Hypalon, PVC or P.U?

You want to repair your inflatable boat, but when you go to buy repair products you are faced with several options!

Is your rigid inflatable boats tube PVC, Hypalon or P.U?

Rib tube material can look the same however to the trained eye its usually not to hard to tell. PVC also known as Polyvinyl chloride is generally a stiff plastic sheeting however by adding plasticiser additives they have made it vastly more malleable, the trouble starts when these additives leak out of the material when hot, old or under UV, this then causes the material to lose its flexibility and begins to deteriorate. the other issue is that there is no UV blackout, so UV rays penetrate the tube and destroy the adhesives. because of this the many manufacturers turned to welded seams this is a very strong mechanical join that will not separate with heat, however it is often harder to repair, and welded areas stiffen, crack or delaminate which will be hard to fix.


  • Shiny
  • Scratch puncture resistant
  • Weldable
  • Cheap


  • Doesn't last long when bonded
  • Welded seams are hard to repair
  • Fabric cracks and becomes stiff
  • Not very chemical resistant

How to tell

  • Is a harder surface material excellent rub resistance. if you try to sand it, it well scratch and score as apposed to sand
  • Will usually have the same colour internally and externally
  • Will soften quickly when wiping with solvent
  • Usually more shiny
  • Look at edges of seams, if they look welded its PVC or P.U

Brands who use pvc

  • Valiant
  • Zodiac
  • Yamaha
  • Honda
  • Mercury
  • Bombard
  • Highfield
  • Ribeye
  • Ballistic
    And many more

Is your rigid inflatable boat tube Hypalon CSM?

Chlorosulfonated Polyethylene (Hypalon) also known as (CSM) is an old material which was stopped production since it it was not environmentally friendly or safe to manufacture it was brought back to life by orca with a new formula (CSM/CR) variant. Hypalon is UV resistant and has a internal UV barrier to aid in the longevity of life, it is not weldable but once correctly abraded the adhesive is able to adhere to it very strongly products can last 20- 30+ years.


  • Great for adhesive bonding
  • If cared for has a very long life span
  • Doesn't stiffen
  • UV resistant
  • Heat resistant
  • Chemical resistant


  • Not the best scratch/puncture resistance
  • Less tensile strength/ tear resistance
  • Adhered seams can come apart in heat

How to tell

  • Less shiney
  • Grey or black internal colour
  • Bonded seams
  • Fine dust when sanded

Brands using Hypalon

  • Cobra
  • Scorpion
  • Henshaws
  • Ribcraft
  • Zodiac (milpro)
  • Revenger
  • Ribtec
  • Delta
  • Pascoe
  • Humber
  • brig
  • ribeye
  • ballistic
    and more

Is your rigid inflatable boat Polyurathane?

Tubes made of polyurethane (PU) are difficult to manufacture and are consequently not often used for RHIB construction. PU has the advantage of being very tough. Earlier PU had a disadvantage of aging quickly but newer types are much more resistant to degradation when exposed to ultraviolet-light. The issue with most of the older P.U built ribs is the UV rays and heat penetrate the fabric and much like with PVC destroys the adhesive bond. More recent fabrics are said to have a black out layer to help combat U.V rays.

While P.U tubes have been thermal welded, fittings and attachments will still usually be bonded using adhesives. when welded it is very strong inflatable but can also have a tendency to crack sometimes and can be very difficult to repair. A high-quality PU-made tube lasts over 20 years. PU tubes are often to be found on commercial RIBs, in applications where strength and durability are needed.


  • High durability
  • Can be bonded and welded
  • UV resistance
  • Scratch/puncture resistance


  • harder to repair
  • Stiffer than other options
  • Doesn't adhere as well as others options
  • Harder to work with than other options
  • Welded seams are hard to repair
  • Welded cracks and delamination hard to repair

How to tell

  • Shiny
  • Can have grey or same colour internal layer
  • Look for welded seams
  • Can often see its larger internal canvas/weave layer
  • Much thicker material

Brands that use P.U

  • XS-ribs
  • Tornado
  • Vanguard
  • Wing inflatables (USA)

So in short: is it P.U, Hypalon or PVC

  • If you can see the inside of the tube, either through the valve or through a rip or tear (you may need a torch). Hypalon is generally dark grey or black on the inside. Both P.U & PVC tends to be the same colour inside as it is outside (allowing for some fading).
  • Lightly sand the outside of the tube. Hypalon will matt down and produce a fine dust. Both P.U and PVC with just scratch and score.
  • If the seams are heat welded (as opposed to glued), then it is PVC or P.U. Hypalon cannot be heat welded.
  • P.U (polyurethane) fabric tends to be far stiffer and thicker material than ether of the other 2 options.


We are based in Yeovil, Somerset but will also work in Dorset, Devon and Cornwall.

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Orca Hypalon info and chart