You can barely use the 11.5 foot if you do not have anything at either end. You should allow 2' on each side for chairs to move in and out. So 11.5 plus 4' for each end chair is 15.5' and no room to walk around the wall end if you are eating at the other side of the table.

My dining room is 16'X13' and my table is 3.5' wide and 8' long with leaves. I am able to have a small table at one end and still have room to walk around. I would barely have room to walk around if it was 3.5' longer and I could not have my table at the end.

Thank you! At one end I will have an 18'' deep buffet, but at the other end, the room is open to a large foyer. We would have it open only for holidays (it seats 14 and we would only have that open when we have a larger crowd). I agree that it would be tight. Would you recommend taping it out on the floor? I think I might do that.

Yep taping would be good. If it is only going to be used for holidays, can it impinge into the adjoining room? It may be that you will have to have 2 tables. My opening is large enough I can add another table at the end into the living room.

Unfortunately, two tables will work size wise, but I think that I'd like to try to find one table that can in fact extend. I don't mind having it extend into the foyer a bit if it will only be for special occasions, but I do agree that taping it out on the floor is probably the best idea. I think I will give it a try on Monday and see what happens. Will report back!

I actually use a large folding table covered with table cloths so you cannot tell. Same height and width. I like using 2 because I can have a "kids" table!! But it is harder to store than leaves.