#### Cleon

##### Adventurer

*robe of infinite twine*yesterday when my random thoughts led me to contemplate the humble hempen rope and a thought occurred to me.

How much weight can a standard hempen rope support? It'd be nice to have some idea how many adventurers can dangle from one before it runs the risk of snapping! For that matter, how thick is the rope?

Since there was nothing better to do this weekend I spent a pleasant few hours thinking about the question and rummaging through the internet on data about rope strength - which proved harder than I thought, since rope made out of hemp or other natural fibres is little used these days.

Anyhow, you might as well enjoy the results of this "research".

**Basic Stats**

**Rope, Hempen, 50 ft. (3/3.5/Pathfinder)**: This rope has 2 hit points and can be burst with a DC 23 Strength check.

**Price**1 gp,

**Weight**10 lb.

**First Approach - Break DCs vs Strength/Carrying Capacity**

A Break DC of 23 means a character must have a Strength bonus of +3 or greater to snap the rope, requiring a Strength of 16 or higher. The

**Carrying Capacity**rules say a character can lift twice their maximum load off the ground and stagger about with it, ergo they are applying a force equal to that weight. A Str 16 gives a max load of 230 lbs so their "max lift" is 460 lbs.

That seems too low, being roughly the weight of two medium-sized humanoid adventurers and their equipment. However, 460 pounds is the extreme edge case. The character is doing their utmost to break the rope and was extremely lucky (rolling a natural 20) to stretch the rope

*just right*so they hit or create a weak spot on the rope causing it to fail. In normal usage that wouldn't be the case.

Instead let's consider a character who can "take 10" on a Strength check but will just fails to hit the rope's Break DC of 23. This requires a +12 Strength bonus so they would have have a Strength of 34 or 35, meaning their maximum load is 2800 or 3200 pounds and their maximum lift is 5,600 or 6,400 pounds.

Averaging that out suggests the standard hempen rope has a breaking load around 6,000 pounds.

That doesn't mean 5,000 pound Cloud Giants can go freely bungee-jumping with standard hemp rope however. That's the maximum load at which the rope is

*sure*to break. The safe load of a rope is but a fraction of this, ranging from one-quarter to one-fifteenth of the breaking load depending on the likely use. For "your life depends on it" tasks good engineering practice recommends a factor around twelve, for a safe load of 500 lbs, especially if the rope is regularly exposed to strain and expected to last a while. However for the risk-casual adventurers a factor of six should be enough, for a

**safe load of 1,000 lbs**beyond which there's a risk of the rope breaking.

Incidentally, merely tying a knot in a rope will reduce its breaking load by 50% or so, since knots concentrate stresses in the rope and make it more likely to break. So a 6,000 lb. breaking load rope will fairly definitely snap if you tie it round a 3,000 lb. rhinoceros and try to hoist it in the air. Going by some of the rope-related websites I read together the loss in breaking strength can be as little as 35% with the right knots, suggesting another task for a Use Rope skill check…

**Second Approach - Real World Comparisons**

Okay, we know 50 feet of this hempen rope weighs 10 pounds, therefore the rope weighs 0.2 pounds per foot (5 feet per pound) or, if you prefer S.I. units that comes to about 298 grammes/metre.

It took me way longer than I expected, but I eventually found enough sources on the weights of ropes made from actual

**hemp**(

*) to determine that's the weight of a hemp rope 20mm in diameter (i.e.*

*Cannabis sativa***Buy Rope**&

**Hemp Shop Rope**), or 13/16th of an inch.

That Buy Rope datasheet gives an estimated breaking load of 2650 kg (5837 lb.) but the Hemp Shop Rope gives 1856 kg (4092 lb.). However the Hemp Shop's rope is 253g/m so is 5/6th the weight of the SRD hempen rope which therefore should be roughly 15-20% stronger, or 2183 kg (4816 lb.), which still is oddly low compared to the other figures I found which were all in the high-five-thousands to mid-six-thousand pound range. For example, this

**webpage (which turned out to be a good general reference source) lists 20 mm Italian hemp rope as having a 2,900 kg breaking load [6388 lb].**

**Smackdock Rope**Overall, 6,000 pounds for the breaking load seems an acceptable compromise, especially as it matches the result of the first approach. What a remarkable coincidence!

For other "hempen" fibres, manila ropes made of

**(**

**abacá***Musa testilus*) appear to be

**almost as strong**as hemp, while sisal ropes made of

**sisal**(

*Agave sisalana*) are

**significantly weaker**than hemp and manila.

**Conclusion**

The SRD standard hempen rope is a 13/16th inch diameter hemp rope that can support 1,000 pounds safely, or up to 3,000 lbs with an increasing risk of it breaking.

**Note**

Since this post is based on an evening of idle internet browsing through the internet, don't use the rope strength for real life applications!