Why is my townhouse damp?

I live in a 36 year old house( my washer and dryer are on the second floor) and when I do my laundry and I use the dryer the entire second floors walls get damp and so do the windows. The machines are not that old, only about 4 years old. Why could this be happening does it have to do with the house not venting it or what? Or is this normal. The townhouse is little small, could that also be the problem or is it because of something else?, please help. Thank You