Seal and Vent, or just vent with occasional flooding?

[jimk]

Like the previous poster I occasionally have standing water in my crawl. My house is about 900 square feet, and the crawl is 4.5 to 6 feet tall. It has a deep 3"-8" gravel base but no poly below the gravel. There is fiberglass insulation between the joists but it is hung upside down (vapor barrier away from the floor) and is mostly falling away. I've been removing it as it falls but want to solve my moisture problems before replacing it. About three to four times a year a strong rainstorm will cause up to a foot of water to runoff into the crawl space.This isn't just gutter runoff, the storm sewers get overloaded and the whole neighborhood has this problem A few weeks ago a hundred year flood in our area left me with 4' of water. It always drains quickly (hours to a day), but pushes the odor of must and mold up into the house.

The good news is I have no electric or HVAC in this space. I am considering 3 options. 1)Adding powered vents to the space but not sealing the crawl space so it can continue to quickly drain when it does flood 2)Completely sealing the crawl and adding a sump pump and dehumidifier or 3)Renting a industrial dehumidifier to really dry out the joists (they have some surface mold but no rot) and then having expanding foam insulation installed to completely fill and cover the joists. This would insulate and completely seal the conditioned space from the crawl.

Any thoughts? I'm in Kentucky, so we have cold winters and somewhat humid summers.

Thanks, JimK

[richard]

Jim K,

OK, you're considering three options for the standing water and moisture problem.

1. Adding power vents simply sucks moist, unconditioned air into your crawl space faster (in the summer, in the winter you wouldn't use it as you would be blowing cold into your house). Air in a house moves from bottom to top -- it's sucked in at the lower levels and is expelled out the upper levels. So the air in your crawl space is moving up into your home, that's why you get the musty smell upstairs that originates in your crawl space.

2. Completely sealing the crawl space and adding a sump pump (http://www.basementsystems.com/sump_pump/) is the way to go. The CleanSpace (http://www.basementsystems.com/crawlspace/) system consists of a 20-mil vapor barrier (so you can store stuff on it, crawl around on it), and a suite of products from vent covers to access doors to wall caps and more, to really encapsulate the crawl space. This lowers relative humidity and makes the home healthier and more energy efficient.

3. The SaniDry dehumidifier (http://www.basementsystems.com/dehumidifier/) and air filtration unit will dry your crawl space, thus preventing mold growth and eliminating musty odors and really drying out your building material. With the SaniDry you can set the relative humidity level to what you want (50% is a good target) and the machine will dry it (up to 3000 square feet at an 8-foot ceiling).

Call 800-638-7048 to contact your local Basement Systems dealer or contact us online (http://www.basementsystems.com/forms/contact.php).

Thanks for the post,
Richard