We have a home that was built in 1920. We want to take an upstairs bedroom and turn it in to our master bathroom. There is a set of windows about 45 X 58. Our contractor says we do not need a fan in the room because of the windows. I told my husband we should do it anyway and vent it out the side of the house. We live in a four season area. So the question is, should we have the fan installed? I'm not one for opening the window in winter and the tub will be installed beneath the window. Thank you.