I have seen 640 square foot homes that I could live very nicely in.

Well, about 1,200 sq ft? May be less Joan Cox .

Actually I was raised in a family of 5 in 230 sq ft in India! So I am asking for too much....lol!

Without my wife, I could easily live in 500 sq. ft.  With my wife, I need 3,000 sq. ft. minimum!    

In 1850 you lived outside and went inside to sleep. Inside was the 'other' place.

In 2015 you live inside and go outside to go to anohter place inside. Outside is the 'other' place.

The former could do a family of 8 in 400 SF.

The latter can't do a family of 4 in 1700 SF.

How small could I go before I become a headline? 725 SF.

If I never had guests I could live in about 800 square feet with only one bedroom.  Of course it would be hard to entertain in such a small house.  I currently live in 2260 square feet with three bedrooms a formal dining room and separate office and living area.

Interesting question. I sell to seniors looking to downsize and find they often buy homes as large as their previous home.

I've lived in less than 500 square feet when I was a graduate student--but wouldn't be looking to repeat it!

Joan, incidentally, I showed a number of 880-1000 SF homes today.  Some were cute as a button and especially with some additional outdoor space very workable for one or two people.  Others were not, it all depends on the layout!

I live in a house in Durham, NC now with a touch less that 1300 square feet. There are a total of twenty legs in our house as well (four humans, one dog, two cats). This space is really tight, and our next house will be about 50% larger. Our situation is helped, though, becuase we have a front an d back yard that we can extend our living in. Or, at least, we had a usuable back yard before we added a puppy to our family this summer...

I like and agree with Gabe above.  I have like comfortable in 635sq ft before getting married.

We're considering a downsize to 2000 sq. ft. now that our kids are all grown and gone. I have a home office and entertain a lot, so that seems like the right size for our next setp. I think it all depends upon your when and family situation. My folks (in their late 80s) are in 1100 for a 2 bedroom. I think I could do that at some future (WAY future) date. 

We just have two cats and a dog, but we also run two businesses out of our home.  A tiny house just wouldn't work, Joan.

When i was working in Atlanta and travelling I lived in a hotel for a month at a time, and I actually was okay with that. Helped the weather was good and I worked a lot.

Joan,

We like a bigger spaces, presently we have 2000 square feet, and we find it small.  We both like to move around and more space.  I admire those that can live in small spaces.  We like to spread out.  A

I like this question, Joan....and wrote a post about living in 200 square feet.  Most people thought that was too small.  I like the 800 square foot houses, but I don't think I could even do that!

There are no tiny homes in our area.

When out on remote projects I can stay in a minivan for months, but my home is fairly large, yet not quite big enough at times.