Behold the invention of the printer! You can turn PDFs into paper in the comfort of your own home!
Seriously, I'd only consider going to the library if I need a whole book (for a single chapter I wouldn't bother, digital or local printing is fine for that) or if the resource is not available in a digital format at all, which is getting exceedingly rare unless I need something really old. Especially if I've decided that I need paper X for whatever reason, then it'd be useful to read it right now at my desk instead of some time later this day after a visit to library.