What is would be a small listening room size?

IMO depends on if a home, or an apt. And if a living room, or a basement.
A small apt room is 10' by 12'
A medium apt room is 11' by 18'
a large apt room is 14' by 24'
I know of luxury apts with 22' by 40' living rooms... That would be giant sized room.
(my apt listening area is 11.5' by 28'.. with an intrusion for a divider behind the listening area)

In a modern home i would expect rooms to be larger than in an apartment.
In an old home, not remodeled, the rooms will be more apt size.
Open plan home may have huge areas.
And way more than 8' ceiling depending
And of course the big homes of the wealthy may also have huge listening areas, though i know some with a small side room for a listening room.. (WAF issues)

Basements are all over the place, due to construction. Most have a lower than 8' ceiling. And if you live in a flood plain, not a good place for a stereo, sump pump or not...

http://forum.audiogon.com/cgi-bin/fr.pl?ymisc&1239284130&openmine&zzWinoguy17&4&5#Winoguy17

Medium.

I use the terms "small", "medium", etc. to reflect a room's suitability for large, high end speakers. Many large, full-range systems produce enough bass to overwhelm a typical 12 x 17 x 7.5 space. Many large planars will physically dominate such a space. In my book, a large listening room can accomodate all but the lunatic fringe loudspeakers.....which need very large ("huge"?, "palatial"?) rooms. IMO, the space the OP describes will probably be too small for best results with a LOT of high end speakers that will work well in large rooms.

That said, when I look at the "systems" links for some 'goners, I see some very large speakers stuffed pretty tightly into smallish spaces, so - evidently - some other might use similar critera and reach a different conclusion.

Marty

Your room is comparable in size to mine. (around 14X19X8)
I consider our rooms small. Better suited for small to medium floorstanders.

Here's a concrete example:

My old speakers, North Creek Eska's, were a slender MTM mini tower designed for near wall placement small to medium rooms. They were housed in 13x13x9h room, open on two sides, and worked very well.

I've moved, and the room is 14x20x8.5h, pretty open on two sides; the Eskas, lovely as they are, pretty clearly lacked presence in this space. I replaced them with some fairly large (150 lbs, 53"h, 2 8" woofs) Montana EPS2s, which work very well. In fact, I think the room could handle larger speakers that move more air.

So based on my experience, the OPs room, of pretty similar size to mine, counts as a medium room that does not limit him to small speakers (depending of course on factors like the desired distance from boundaries.

YMMV, of course. Interesting that there are divergent strongly held opinions on this issue.

John