funny smell after crawlspace encapsulation

[ironpony]

install a "radon system" and move the air under the plastic, it will dry everything out. This is a common feed back from our customers, along with their dehumidifier runs a lot less. Costs a lot less than a dehumidifier to run and the dehumidifier will not dry out the sub grade under the plastic sheeting.

 

[RustyShackleford]

install a "radon system" and move the air under the plastic, it will dry everything out. This is a common feed back from our customers, along with their dehumidifier runs a lot less. Costs a lot less than a dehumidifier to run and the dehumidifier will not dry out the sub grade under the plastic sheeting.

Wow, never thought of that. I guess it'd help if my problem is "soil gas".

I think I've read it's just an H-shaped arrangement of perforated PVC drain pipe (2 or 4" ?) and then a fan.

 

[ironpony]

actually you can just use a roof boot to attach to the plastic sheeting. slit the plastic and slide the roof boot under the plastic and glue in place with 3m contact adhesive. if you slide a pipe stub thru the boot before you attach it, it makes it easier. we use all 4 inch pipe but 3 should be fine. we have found no difference in efficiency with or without the perforated.

 

[RustyShackleford]

actually you can just use a roof boot to attach to the plastic sheeting. slit the plastic and slide the roof boot under the plastic and glue in place with 3m contact adhesive. if you slide a pipe stub thru the boot before you attach it, it makes it easier. we use all 4 inch pipe but 3 should be fine. we have found no difference in efficiency with or without the perforated.

No foolin', so you don't have a network of pipes under there, just one opening like that ? My crawlspace is about 28 x 60 ft. And then a pipe from there to a fan which is sucking air, and blowing out through a hole in the crawlspace wall somewhere ? Is there a link that'd show the whole thing ? Thanks !

 

[TradEddie]

I'm not talking about running AC (not sure what you're talking about, maybe my answer in post #21 ?) I'm talking about a separate dehumidifier in the crawlspace. Though in fact the code requires (and there is) a small outlet from the HVAC supply into the crawlspace; but it obviously ain't enough to do the job for me.

It was others suggested that a/c would help, I couldn't see how, but if there is a small outlet, it would help some. Radon fan might help if the problem is ground moisture, but won't do much if the problem is just outside atmospheric moisture. If you do need the humidifier, experiment to see how low a setting will do enough to eliminat ethe smell.
Lastly, speaking as a microbiologist, even with really high humidity, mold needs something organic to grow on, starve it as well as dry it out. Don't have cardboard boxes touching walls or the ground. If you use a disinfectant, use a good one with residual action, using bleach or those ones with only citric or hydrochloric acids will only kill, but won't stop it growing again.

TE

 

[ironpony]

nope, you can split it into 3rds and use 2 roof boots if you want. pipe to a fan, exhaust thru the band board. Use a dryer vent outside and it will blend right in. Google radonaway and buy an rp145 fan about 100 bucks. 5 year warranty, very quiet and uses little electric. Also ul listed for his use.

 

[RustyShackleford]

Radon fan might help if the problem is ground moisture, but won't do much if the problem is just outside atmospheric moisture

Yeah, the atmosphere is pretty damn moist here (for 6 months of the year, at least). The soil is too, but there's a good vapor barrier on top of the soil, whereas I know the sealing around the band-joist is (supposedly) sub-standard. I'm intrigued by Ironpony's suggestion, because a simple inline fan is going to use a lot less electricity than a dehumidifier, even a high-efficiency one; but I wonder if his experience necessarily translates to NC (not sure if the experience he's talking of is in Ohio or where).

speaking as a microbiologist, even with really high humidity, mold needs something organic to grow on

Would wood be organic enough ? I know there's some white staining on the joists from back when there was condensation all over the floor insulation batts (before I laid down some plastic half-assed, which was before this "encapsulation" job).