VENTILATION FAN UNDER HOUSE
QUESTION: We had some settling of our foundation along one wall of our house and had a foundation engineer evaluate the situation. One of his suggestions was to put in a ventilation fan under our house crawl space to keep the moisture out. We have no water runoff underneath just a large deck right next to this area that stays damp underneath. He suggested we call a Heating and AC company for this type of fan or go to Home Depot and get a large fan.
Needless to say, the two Heating and AC companies I called never heard of such a thing and I would have no clue as to what kind of fan or even where to put it if I just went to Home Depot. Besides that, running a fan whenever it was damp underneath our deck would mean that it would always be on. Our SMUD bill would be out of sight. Can you help me out as far as where to go next?
M. Terra, Sacramento
ANSWER: “The fans are a good option for an occasional dry-out but they certainly don’t sound like a good permanent fix.” says Vince McDonald of McDonald Plumbing, Heating and Air Conditioning in Sacramento. “It sounds like you need to go after the cause of the water rather than treating the symptoms,” he says. “My suggestion is to consult with a general building contractor, landscaper and or civil engineer.”
“What is the saying, ‘an ounce of prevention is worth a pound of cure’? If you prevent the water from going into the area then you won’t need the fans. If you have no leaks under the house I would suggest that you inspect and evaluate how the water from rain and irrigation runs away from the house. Pay particular attention to the downspouts and water that is shed off the roof. We commonly see downspouts terminating at a point next to the foundation and the slope of the surrounding ground prevents this water from running away from the house. If water is trapped and cannot naturally run away from the house due to the landscaping and lay of the land, then consult with a landscaping contractor to design and install a storm drain system to do the job. If it is fairly complicated, it may be best to also consult with a civil engineering firm.”
If you have any further questions please contact McDonald
Plumbing, Heating and Air at (916) 233-4194.