crawl space solutions

[washman9]

i am in the process of researching how to best approach a problem with moisture and mold in our homes crawl space. look at sealing the space, closing off the vents and installing a crawl space dehumidifyer. i have not gotten a professional estimate and as most wash owners feel i can probably do it myself for much less. i may be wrong and the cost-time ration may not be worth it for me. just curious as to anyone out there who has any experiences.

 

[mac]

Closing off the existing vents sounds like a bad idea. Even with a dehumidifyier. My guess is either the vents are plugged, or they were not sized properly to begin with. You should have a large vent on the top and soffitt vents all along the perimeter. If you have had blown insulation added recently, they most likely blew it over the soffitt vents. The top vent should be a ridge vent which runs across the entire length of thr ridge. You still see some turbin vents, but these can blow off in a strong storm and then let water in. This will be a simpler and cheaper alternative than adding a mechanical device.

 

[Parker]

if you have a ridge, gable end and soffit vents then that could cause it. usually good to go with 2 not all three preferably ridge and soffit, dont know why but it seems to disrupt the air flow. you could always try just blocking the gable end vents to see if it works. but i would agree blocking the vents would be a bad idea...

 

[Skipper Jack]

You mentioned crawl space, but Mac and Parker seem to be talking about attic space. Crawl space always meant under the house to me. If so,

Is there a vapor barrier on the ground?

What about increasing air flow, there are fans that replace the standard vents.

Finally, what about leaks? A persistent leak would certainly cause moisture problems.

 

[washman9]

i am talking about the crawl space under the house. i do have plastic down. in our part of the south there is constant humidity and moisture. we notice the moisture is better during the dead of winter.

 

[Eric H]

my understanding is that a vapor barrier with seams overlapping 6 feet and taped is the way to go.

I'd post here:
www.forums.woodnet.net/ubbthreads/postlist.php?Cat=&Board=UBB3
or do a search for crawl space vapor barrier.
Many of the guys there are very knowledgeable.

 

[dclark3344]

I once owned a house that they had added on to the living room. They also pored a concrete porch and only had one vent in this addition, which abutted to the original stem wall. Well the floor rotted and fell in and had to be totally rebuilt. We also installed french drains around the perimeter because of water building up around the house during heavy rains.

 

[Tom Thumb]

I have had several homes in the south and it has been my experience that you must first determine where the mold is coming from, you need good ventilation , a barrier on the ground, and I would cover the ground with lime before laying the barrier.
Where I lived we had clay type soil.
Hope this helps.