Dry Out a Damp Crawlspace
LESLIE: Now we’ve got Tom in Anchorage, Alaska who’s dealing with a possible mold situation. How can we help?
TOM IN ALASKA: Hi, guys. Yeah, I’ve got a crawlspace – it’s about four feet high – and I’ve got this musty smell down there.
TOM IN ALASKA: And I think, you know, I haven’t seen any mold but I’m thinking that, you know, sounds like there might be some there. So, you know, looking at maybe trying to wipe it down and get rid of the smell and then what I can do to treat it, as far as keeping it from coming back. I’ve got viscuine down there; you know (inaudible) plastic down on the floor and I haven’t had any moisture per se.
TOM IN ALASKA: But it’s – you know, we have a wet season that things get real wet. So …
TOM: Well, let’s start with the basics, Tom. First of all, make sure that you are keeping that as dry as possible by paying careful attention to your exterior gutters; making sure that they are clean; make sure the downspouts are sloped away from the wall. And then take a look at the slope of the soil around the house. Make sure that’s also sloping away. Those two things will keep the moisture to a minimum inside.
Now, you say that you’re concerned about mold but you’re not sure that you have it? I don’t want to give you advice to treat something that doesn’t exist. Do you have any evidence that there’s a mold problem down there now or is it mostly just the humidity issue?
TOM IN ALASKA: Well, it’s mostly the smell makes me think …
TOM IN ALASKA: … that there ought to be something there. It’s kind of a musty smell.
TOM: Well, that doesn’t …
LESLIE: What about adding a fan? Like a vent fan?
TOM: Yeah, exactly. That’s exactly what I was going to suggest. What you might want to do is get a crawlspace vent fan. These fans are exactly the size of a concrete block. They’re 8×16. They fit inside of the concrete block and they’re hooked up to humidistats. So whenever the humidity becomes high in the crawlspace they automatically come on and they draw drier air across the crawlspace which will make it less humid and eliminate that damp smell at the same time.
TOM IN ALASKA: OK. Now I had heard something about like wiping down the walls with a Clorox solution and I’ve got a wood foundation stem wall. It’s a treated wood.
TOM IN ALASKA: And I was wondering if there’s any safety issues with using Clorox on that treated wood.
TOM: No, there isn’t but there’s a new product out that is applied with a fogger that you might be interested in. It’s called Concrobium mold control; spelled C-o-n-c-r-o-b-i-u-m. It’s sold at The Home Depot and you have to get it in the rental center because you have to rent a fogger to put it on. But basically it’s a new, nontoxic material that has a formula that sort of encapsulates the mold and the fungus and so it will inhibit any mold growth. So it’s OK on the wood wall and it’s OK on the block wall as well. So if you want to be extra safe and make sure that you nip it in the bud, if it’s getting started, you might want to do the mold treatment down there. But also, don’t forget to pay attention to those drainage issues because that is the source of many, many mold problems.
LESLIE: Look at your overlaps on the viscuine that you’ve laid down on the floor. When you’re butting up the seams or laying two joints together you want to make sure that you really overlap one piece over the other by a good two feet so you’re not getting any sort of leakage through there as well.
TOM IN ALASKA: Painting that like with KILZ or something after I treat it, after I fog like the floor joists and the bottom of the flooring above – you know the …
TOM: Generally you don’t paint your floor joists and I don’t really think that that’s necessary. I think if you control the moisture, do one treatment, you should be good to go.
TOM IN ALASKA: Great. Hey, appreciate it, guys. Thank you much.
TOM: Thanks so much for calling us at 888-MONEY-PIT.