Your issue is condensation forming which is caused by too humid of air hitting an area that allows it to reach dew point. Unfortunately you are missing to much information like is it slab on grade, crawl (sealed or vented - vents should be closed) or basement. What is in the sun-room - a bunch of plants, or... What is the temperature you keep the room & what is the humidity level? The answers to this can help you get the best answer for the issue. In short though you need to reduce the amount of moisture in the air &/or raise the temperature of the floor / condensing surface. This maybe done with air-sealing & insulating underneath, dealing with the moisture sources, reversing the fan to direct some of the heat back down, using a full size rug, or a host of other measures. While this piece is directed at "sweating" toilets, some of the advise may help you: http://blog.sls-construction.com/2012/building-science-sweating-toilets
How do I prevent my tile floor in my sun room from sweating now that it is winter and the heat in that room is on?
How do I prevent my tile floor in my sun room from sweating now that it is winter and the heat in that room is on?Asked by Dan
The heating unit is a wall mounted electric one and the room has a cieling fan.