Ropes – Kernmantel or Hawser Lay ?

By Jon Bloor •  Updated: 31-Mar-24 •  2 min read

Hawser Lay Rope

Pros

  • It is cheaper than Kernmantel rope.
  • It is easily inspected for damage.
  • In an emergency, the three strands can be unwound and joined to give a rope three times the length of the original. This is however much weaker than the original.
  • It can be easily washed (like Kernmantel)

Cons

  • It is heavier than Kernmantel rope.
  • It is prone to kinking and is generally less flexible than Kernmantel.
  • It absorbs more water than most Kernmantel ropes.
  • More rope drag is felt when hawser lay is pulled across a surface or through a karabiner, than Kernmantel.
  • Hawser lay has a high extensibility under a normal static load.
  • Full weight hawser lay (No. 4) is not as strong as the equivalent weight (11mm) Kernmantel ropes in use today, and does not meet the same exacting UIAA standards.

Hawser lay is good as an occasional weekend outcrop rope, but none the less seems to cause a lot of aggravation! Make your own mind up!

Kernmantel Rope

Pros

  • It is lighter & usually easier to coil than hawser lay
  • It absorbs less water than hawser lay (normally). This is especially advantageous in wet/freezing conditions.
  • The outer sheath (mantel) protects the important inner filaments from abrasion.
  • It is much easier to use in situations where rope drag is unavoidable, it will slide over rock and through karabiners more easily than hawser lay.
  • It has a high extensibility under shock loading and a low stretch under a normal static load. Hawser lay will often stretch up to 20% of its normal length under a normal static load.

Cons

  • Like Hawser Lay it has a low melting point, being made of nylon. It will quickly melt if a similar rope is pulled across it.
  • Internal fibres cannot be checked for wear.
  • Frequent washing is required to remove grit etc.
  • It deteriorates un ultra-violet light (the sun), as will hawser lay, if it has prolonged exposure.
  • As it is a relatively soft rope, the outer sheath will eventually wear if it is repeatedly dragged over a rough surface.
  • It is more expensive than hawser lay.

Jon Bloor

I'm a leader with more than 30 years of experience and I have run beavers, cubs, scouts and explorers. I was in a trial group for the scout network. Presently, I am group scout leader (or group lead volunteer) at 4th Ashby Scout Group.