LESLIE: Now we’re talking to John in Nevada who listens to The Money Pit on KBZZ. What can we do for you today?
JOHN: Well, a few months ago I had a radon test done in the house; the first level of the house. And the level came back about 4.1 and I know they say anything above four you should probably look into it having it mitigated. Well, I thought possibly I could put a couple more vents in the crawl space in the house to help maybe alleviate the radon.
TOM: Where was the radon test done, John?
JOHN: It was done in the first – in the family room on the first level of the house.
TOM: Huh. Wow. That – you know, that’s very unusual when you’re over a crawl …
LESLIE: Because usually they’re below-grade rooms.
TOM: Yeah, when you’re – when you’re over a crawl space, it’s very unusual to have an elevated radon level. Do you have any stone fireplaces or anything like that in there?
JOHN: No, uh-uh.
TOM: Hmm, OK.
JOHN: I live – where I live, outside of Reno, is a very rocky area.
JOHN: And some of my neighbors have had the test done and one of my neighbors has had it as high as 10 in his living space.
TOM: Well, you’re kind of borderline and what you’re going to find is that those short-term tests – if you did a charcoal canister test –
TOM: – those are short-term tests and normally you’ll get a 50 percent swing in the reading. So when it’s cooler out and the house tends to be sealed up more, sometimes it’s going to be – that’ll be your seasonal high. And in the spring and the fall, when you have the windows open a lot, it’ll be at its lowest point.
Repairing this, though, is the same thing you would do if you had a basement. The way it’s done is the surface of the soil on that floor will be sealed. Now, do you have a concrete slab in that crawl space or is just dirt?
JOHN: No, it’s dirt. Now, what I did is put some viscuine over it …
TOM: (overlapping voices) That’s a smart thing to do.
JOHN: … when the house was built.
TOM: Yep. If you put viscuine over it and if you sealed the viscuine to the block walls, so you actually have sort of a gasket …
TOM: … that would be a smart way to do it.
TOM: And I would do that first and then I would retest. I don’t – not so sure that you need to put in additional vents.
JOHN: OK. Alrighty. I just – is there anything about code? Do codes vary throughout the country, as far as the number of vents you can have in your house?
TOM: You couldn’t really have too many vents.
TOM: So you certainly could do that. But before we start telling you to cut open your block wall, I think if you cover the entire surface up which that radon gas is emanating through, that this problem may go away.
JOHN: OK, I’ll try that then.
TOM: Alright, John. Thanks so much for calling us at 1-888-MONEY-PIT. 888-666-3974.