This is happening with at least two of my custom modular stairs (Chrissy6930's Mission Stairs and one of the converted stairs from Castaways). I'm building beach lots so the stairs are longer than usual. When viewed in lot view, everything looks fine, but when I get out of the lot, they've exploded like when a fat mesh goes wrong on clothing. It does not seem to happen if I don't put on the side rails.

Has anyone encountered this problem before and knows how to fix it? I've searched several forums and found no other cases.

It looks like the mesh with the railings is broken.

I know I've had this problem before... not sure if there's a solution without actually editing the mesh of the stairs themselves. Using LazyDuchess's improved Lot Imposters might bypass the issue, though.

Could be an issue with the LOD that shows in the NH view (not sure if stairs have LODs? Or maybe morphs, for the railings? I don't make them so haven't studied the files much, but I'd think it's one of those).

Stairs render the LOD in hood via the shpe, they don't have separate meshes.

Edit: I just checked the mission ones in my game, and they are fine in hood view. Is your graphics card struggling?

tried the improved lot imposters. i could be doing it wrong or have a conflict, but it doesn't seem to be working. my graphics card really should not be struggling with this. it runs much more impressive games than ts2.

i'd never had this problem with the mission stairs before either. i've been using them for years. it's only since i used them for this extra-long stair down to the beach that it caused the issue.

I had spikes on things right before my old graphic card died. Unless it does this for everyone, then I would say its your PC.
Try dusting out your PC/laptop, overheating can also cause things like this.

Maybe a glitch from the stairs being longer than usual. Does it happen if the same stairs are used in a shorter format?

it doesn't. that's the weird thing and why it's never been a problem before. i've got the same stairs at regular length on several other houses in the same neighborhood.