Hi all So, my NJ basement has a dehumidifier running. Basically runs constantly in the summer What I am noticing is that the basement is really dusty when the dehumidifier is running--really dusty. I am guessing due to the amount of air being moved around. I know that option 1 will be to empty out the basement and deep clean the whole thing (unfinished, cement floor, but a TON of stuff down there)-- this is not something I am eager to dive into, particularly with my back issues I am wondering if there is any benefit to a possible option 2-- either replacing the current dehumidifier with a HEPA filter equipped version-- or just buying an air filter and leaving it on down there. My wife has been experiencing allergies ever since we moved into this house. We had the ducts cleaned to try to alleviate them, and it helped, but she still has some issues. I suspect the basement dust is being pulled into the ductwork. I also need to tape/mastic the joints down there. Anyone have experience with this? -K

Hello, I have a two-story contemporary home built in 1982 located in coastal Virginia (Zone 8A, hot and humid summers). Crawlspace is 1480 sq. ft. and is approx. 28" high. The exterior walls are cinder block. There are no HVAC components or ducts down there, only plumbing. Here's what it was like when we moved in 3 years ago: - 7 exterior grill vents - No living space to crawlspace vents. - Joists had been repaired due to moisture damage, the new joists are sistered and the work was done correctly. - There was and still is a 6 mil. vapor barrier down but it is perforated (1/2" holes every 12"), I assume it was done to allow any standing water to escape down into sand base. - Fiberglass insulation was previously installed but had been removed from floor joists. No wall insulation. - High humidity levels, 85% during the summer was common. Wood moisture readings were high as well. - Some light mildew/mold (mostly white fuzzy stuff) was growing on old and new wood. - No obvious signs of regular water intrusion, we did get 4" water in there during Hurricane Matthew but that was 15 inches of rain in 24 hours and def not the norm. We are not in a flood zone. - Outside gutter downspouts were only draining 1-2' from foundation. Here’s what I’ve done: - Had 3 crawlspace companies come out to inspect. 2 recommended full encapsulation with dehumidifier, french drains and sump pump ($15k-$20k). The other recommended that I simply seal up the vents, get a dehumidifier and see how moisture levels respond. - So I sealed the vents and got a dehumidifier with pump (Santa Fe Compact 70). It drains outside of house. - I moved all gutter downspouts so they drain 3’-4’ from foundation wall. - Humidity levels stay between 45% and 50% year-around and wood moisture is approx. 13%. So now here’s my issue. The inside of our house gets a musty smell, especially when humidity rises. This was not noticeable when crawlspace was vented so pretty easy to assume that crawlspace air is getting pulled into living space since it has nowhere else to go. I contacted another company to come take a look, he recommended a new vapor barrier to replace the perforated and poorly installed one and to remove the dehumidifier and vent covers. Basically go back to the way it was previously but this time with a new vapor barrier. I raised my concerns about previous humidity/wood moisture issues and he said they would be minimal and that the vents would do enough to circulate air and prevent smelly crawlspace air from getting into living space. He said that’s the only way to get rid of the musty smell. Here are my thoughts/ideas… - I realize new vapor barrier is needed and it will be replaced. Would that be enough to reduce musty smell? - I’m hesitant to open vents and raise humidity/wood moisture levels again. - I’m assuming air is getting pulled up into the house via the stack effect, especially when HVAC is running. My crawlspace dehumidifier has the ability to be ducted outside (it is not currently, the air is being filtered MERV-11, dehumidified and sent back into crawlspace). The blower is 150 CFM. would that be enough to reduce stack effect and reduce air being pulled into living space? Thanks for any insight! Dave