We have a small room in our attic that has been converted into a bed room. I noticed condensation on the walls when it's cold outside. The RH is 65% at 62 degrees. The rest of the house (1st floor) is 35% RH at 65 degrees. When I use a dehumidifier to bring the RH down to 50%, the room is fine. No condensation what-so-ever. Why is this room humid? We've had the house for 16 yrs and the problem has just recently appeared. We got a new oil burner 4 yrs ago. It is stronger than the old one and keeps the room warmer. In the past, we used a space heater for extra warmth. We have a forced hot air system. Could this be the source of the moisture? The attic itself is well ventilated. I'm pretty sure it's not the insulation trapping moisture. I think something is adding extra moisture into the room. Any thoughts? This is the second yr I'm dealing w/ the problem. Over the summer I replaced an old ridge vent and added a new one in the hopes of solving the problem.