When I hear "sunroom" I think of old brick, saltillo pavers, old painted wood, parquet wood pavers,or concrete pavers. However, nothing beats the utility of tile for your situation. They even make tile that looks like old bricks or wood. You can always add throw rugs in strategic spots---and have under floor heating for the winter months.

Tell me more about the old painted wood. How terrible would that be? The old houses around here (and there are way more old houses than new where I live)are almost entirely floored in wood even under their claw footed tubs. The rental house I'm in has oak in the living areas and bedrooms and beautiful heart pine in the kitchen. The laundry's in the basement. Few houses here had dedicated laundry rooms, though some have converted back porches.

I don't see why you couldn't use painted wood. I'm sure it could be sealed by a poly product of some kind. I would talk to some floor people and get their take on it. I would think the marmoleum would be good too; I love all the colors and designs plus it should be very durable.
Let us know what you decide!

I grew up with a painted wood sunporch. It had to be repainted every 3 years or so, and you had to be really careful about watering the plants because of potential water damage. Painted wood is higher maintainence than any of the other choices, and yet isn't as durable. You will begin to see traffic wear patterns within a month or two. Coating it with poly just makes it worse to try to repaint. It's a good look if you like patina and you are willing to put down rugs in high traffic areas. If you are someone who doesn't like the weathered and worn look, then painted floors aren't for you.

You might also investigate "limewashed" or "bleached" wood as that changes the color of the wood itself to a lighter tone rather than just being a surface coating. Conventional floor finishing techniques cn be used after treating the wood, just like a stain.

I still think a brick or wood look tile will work the best and be the easiest to deal with long term. :)

Then painted wood it is! That sounds exactly what I want. I want it to look instantly worn and lived in. It fits my vision perfectly: a few rugs from the flea market and my grandmother's quilt on the daybed, an old beat up soapstone utility sink salvaged from a school. Now if I can just figure out how to make the windows look like they have layers of paint on them! LOL

I know you keep pushing tile, live wire, and I know it is the most durable, but it is the one flooring that I'm sure we won't do. It is too hard to stand on, and I don't want to cover my porch with gel mats. Painting at the easel or ironing would be miserable standing on tile. I also work a lot with glass and tile is unforgiving. Not to mention how cold it would be, because we certainly won't be putting in heated tiles. I'm not even putting tile in the bathroom, but I did convince dh that we should put tile in the back hall (mudroom) since we won't be standing around there for any length of time.

A linoleum product may still be in the running. I do like the "green" aspect of cork but I'm afraid it won't be right for achieving my old house look that I'm going for.

Be sure you prime the floor and use a high quality porch paint, not regular enamel. You shouldn't have any problems. I painted the front porch of our 100 yr old Arts and Crafts home, and it looks great 3 years later. Not a sign of wear. And it's outside. It hadn't been done in probably 20-30 years, so looked pretty bad.

Another option to consider is vinyl tile. I know, it sounds cheap. But we put Armstrong Alterna luxury vinyl tile in our new multi-purpose room (laundry, my office, etc), and I absolutely love it. We had them lay it with no grout line (HATE GROUT!), and it's fantastic. It's thick, heavy duty, and should last forever according to the guy who laid it. It is a floating floor.