gyms requiring 35m ropes where 30 would be plenty

Both gyms in my area (run by different companies) have signs requiring 35m ropes in their lead areas - even though their longest most overhanging routes would work with a ~28.  I.e. a 30 would be fine with room to spare - so even if they put up a route that is both overhanging and significantly diagonal (which they don't seem to actually do), nothing catastrophic would happen.

At first I thought it might be a way of (falsely) advertising themselves as having longer routes, but at least one of them describes their walls as 45' on the website.

The best reason I can imagine is they don't want to deal with stuck-2-ft-off-the-ground-while-lowering people who (1) tied their fig 8 with a huge tail, (2) tied a stopper knot several feet from the end, (3) climbed the longest possible route that may not actually exist, and (4) are unlucky enough to have a rope that's exactly 30 (as opposed to 31-32 as most ropes sold as "30" would be). Seems possible but far-fetched.

Another reason that would be kind of understandable (but, as far as I can tell, a myth) is believing that ropes shrink 5% with age.

Has anybody come across better explanations ? Would insurance companies influence this ? Is the same thing happening in other places ?

I also noticed 30m ropes are harder to buy than they were a couple of years ago.  If these 2 effects are related, I wonder which caused which.

Insurance. Idiot proofing. The routes are longer than your estimations. All of the above.

Aren’t the commercial “gym ropes” usually 40m? But that is an annoying requirement. Do they bust people and measure the rope? I’d write over or take off the end tag.

Is anyone actually measuring the length of ropes? Why does this even matter?

Someday they might set a mega-traverse that uses more rope. Tie a knot in the end if you use a short rope in that scenario!

Connor Dobson wrote:

Is anyone actually measuring the length of ropes? Why does this even matter?

This.

"If you make something idiot-proof, someone will just make a better idiot." As such, 35m ropes when a 30m would likely do.

Seems reasonable to me. In the real world people always manage to find odd ways to f*** things up. For example, what if someone did all of the things you enumerated plus had the belayer standing a bit too far off to the side or away from the wall… (plus potential rope shrinkage you also mentioned…) And then they forget the stopper knot. It’s probably just a way to make sure there are as few issues as possible with us error-prone humans. In our local Sharma gym I suspect a 40 meter rope would be just fine, but I use a 50m gym rope and the extra 10m is really not an end o’ the world hassle—plus I’m ok if I go to a gym with slightly higher walls, and I can use the cord on short outdoor sport routes. 

Rope shrinkage? Like if you cut the rope? Or is it when the rope gets out of the pool on a cool day? Usually there’s a bit of rope stretch with a dynamic rope.

With the trend of gym climbers failing to tie catastrophe knots in the end of their rope AND the trend for climbers to just grid climb the grid bolted wall... it makes sense.

Desert Rock Sports wrote:

With the trend of gym climbers failing to tie catastrophe knots in the end of their rope AND the trend for climbers to just grid climb the grid bolted wall... it makes sense.

Haven't gyms always been grid bolted? Isn't that kind of the point?

It's their house, their rules. As long as it doesn't make it less safe, I'll do whatever it takes to enjoy a climb. The key is less safe. If they want a longer rope. Sure. If I can only 80's purple spandex before the noon hour, great. 

I understand gym paranoia with potentially-high-consequence issues, but this seems different.  If some unlucky party did manage to stack every possible rope length disadvantage against themselves, the consequences would be about the same as falling before the 1st bolt.

35m gives you enough wiggle room to belay like an asshole and not drop your partner. Also, in the case of longer ropes you don't need a knot in the end of the rope that could forget to be untied and get stuck at the anchors. In short, because they say so and I don't think I've ever heard of a gym checking the length of ropes other than the ones they lend/rent out.

Don't folks just use an old lead line for their gym lead rope?  My current "gym rope" is an old 60m lead line with about 10m cut from each end.