Published on January 29th, 2013 | by Henri0
Dampness in lower level of raised ranch
Q. I live in a raised ranch house and am concerned about the dampness in the lower level during the summer. My son’s bedroom is on the lower level and he suffers from allergies. Short of air-conditioning, how can I alleviate the dampness? I do have a dehumidifier, but the upstairs windows are open. I am unable to close off the downstairs level, so I’m basically trying to dehumidify the great outdoors if I run it.
I know that the builder did not put in footing drains. The house is over 30 years old and the builder, so I hear, was not highly qualified. Does a lack of footing drains have any bearing? My house is heated in the winter with an oil furnace and a baseboard/hot water system and is plenty air tight. I would appreciate any guidance you can give me. I read your column regularly and enjoy it and learn from it.
A. The absence of footing drains should not affect the level of dampness you feel in the summer unless you suffer from leakage anytime it rains or when the snow melts. Lower-level dampness is usually due to warm, moist outside air getting in a cooler space such as the lower level of a raised ranch that is kept cooler because it is in contact with earth that takes a long time to warm up.
Air conditioning is one answer, albeit expensive to install and operate, but a high- capacity dehumidifier should also greatly help. I have a similar situation, having a two-story house with one side against a bank, and the dehumidifier keeps the lower level free of the smell of mildew.
Can you close the windows during the day while you are at work so the dehumidifier has a chance to catch up? And can you simply install some form of hanging curtain at the top or bottom of the stairs during the summer to isolate the lower level to some extent?