Automatically make footnote-carrying pages vertically stretchable

Question

My thesis use a page size that is exactly 34 line of text tall. (10pt text + 33 * 18pt \baselineskip = 9in plus 2pt, which looks like 1in margins on an 8.5x11" page). Some pages contain pretty much solid text, with some footnotes, which makes them have zero vertical stretchability. The footnotes, though, don't work out to a height that's a multiple of \baselineskip. As a result, LaTeX complains about lots of underfull \vboxes.

Is there a way to make the vertical gap between the last line of text on a page, and the top of the footnotes area, stretchable? I don't want to make my pages use \raggedbottom directly, because then the footnotes slide up to the bottom of the text, leaving a (surprise!) ragged bottom to the page. I want the footnotes to be flush-bottom, and I'd like there to be roughly 1 \baselineskip of stretchable space between the text and the footnotes, so that TeX stops complaining :)

My current attempts, in case this helps: In the thesis class file, it defines \footskip as

\footskip\z@

So I tried playing games like

\addtolength{\footskip}{0pt plus 18pt}
\typeout{\the\footskip}

But that outputs 0pt with no plus 18pt... Is \footskip not stretchable? Or is this the wrong page dimension to be tweaking? Or is there simply a better way to be doing what I want to do?

Answer 1

After a bit more searching (thanks @egreg for helping me cut off a fruitless avenue of hacking), it turns out there exists a package that does exactly this:

\usepackage[bottom]{footmisc}

Good to know :)