Be sure to look at the image in my first comment there - it's pretty juicy, and even works along curved paths. My favorite is my own InsulBattPoly.lsp, available here. If, on the other hand, you actually want a squiggly Polyline end result, rather than a Hatch pattern or via AutoCAD's Batting linetype, there are a variety of routines that will do that. That pattern is defined at 100 drawing units 'high' per row of squiggles, so use a scale of the thickness divided by 100.
If you mean you want a single row of that pattern, such as to show insulation in a wall, you can do it with some care about the boundary, scale and origin, and of course the rotation angle when the wall direction isn't horizontal. Yes, you can do that with the Hatch pattern.
