Late last fall, we had a sunroom built on our nhouse, and we're trying to determine what type of flooring should be installed. We live in Winnipeg, Manitoba, Canada, so the climate will definitely be a factor.
The flooring is plywood, with metal flashing around the outside edge at the walls.
In January/February, the temperature can reach -35C (-31F). In July/August, the temperature can reach +35C (95F). The sunroom is south-facing, with all glass/aluminum walls, so the air temperature inside during summer will be higher than that. In winter, the sun won't have any significant moderating effect on the temperature.
Compounding this, we have a dog that we let out into the back yard every day, so we walk through the sunroom two or three times every day, winter or summer. In winter, this lets a lot of moisture into the sunroom, which condenses on the windows. As we get closer to spring, the moisture melts and pools at the edges of the sunroom, and wicks onto the plywood if I don't mop it up quickly enough.
We have been told that some flooring types won't be suitable (linoleum and vinyl, I think) because they get brittle in our winter temperatures. We were expecting to have to use some outside carpet, but one flooring company told us we could use laminate flooring. I'm getting a sense that the contractor is a bit of an amateur, though, and I've read that laminate flooring contracts in the cold, so I would expect it to shift as we walk on it.
Can someone please recommend types of flooring that may be suitable for our conditions? I plan to have whatever we choose professionally installed (I'm not very handy).
To clarify, the sunroom is a raised structure with insulation in the floor and ceiling. It is an unheated space, and with the temperatures we get in the winter, no amount of insulation will help an unheated space in January. The structure seems quite secure, with teleposts of some kind on top of concrete footings.
EDIT: Not enough reputation to comment on my own question. My installation does not have any sort of pan. The walls are mostly glass with a metal frame, which stands on metal flashing. The flashing extends 5" from the glass/metal walls, and the remainder of the floor is plywood. Since we open the door from the kitchen several times a day to let the dog in and out, the air in the sunroom, which would normally be very dry in the winter, ends up having a lot of moisture in it, which condenses and freezes. In the spring, as the sun becomes more intense, the condensation melts and pools at the base of the wall. I mop it up every day to reduce the amount that can condense that evening, but a couple of times it has reached the plywood before I got home. My thought was to install whatever flooring type is best, then put a barrier of some sort (metal or plastic edging), then add a bead of silicone along the entire edge, to force the water to stay on the flashing until I can mop it up.