Don't know about engineering, but yeah, I'm in law a fair bit, but that's cos I use the books there, but for general purposes, the bio-med section (if it is still used for that) makes for a good area, normally close to silent and relatively comfy chairs for a library, so it also doubles nicely for a place to nap, which can turn into a longer sleep which can turn into you missing out on the first half of a two hour seminar and deciding that it's not worth going to the second half and so you just go home - or so I've heard.