Crawl Space Ventilation in Asheville, Columbia, Greenville, Elberton
How Crawl Space Vents Affect Crawl Space Humidity... And Why
Crawl space vents can usually keep out mice and rodents, but do they really get the job done?
Crawl space ventilation is the answer that contractors have historically given to the issue of crawl space humidity in homes.
This usually involves installing vented openings in a cross-sectional area equal to 1/150 of the floor area served.
These crawl space vents are usually fitted with a covering which is usually a wood, metal, or a mesh covering.
The covering is installed to prevent rodents and animal infestations, but they cannot prevent rodents or insects all together, because of the slats in the covering.
Crawl space ventilation moves outside air through the house, affecting utility bills and health.
The Theory Behind Vented Crawl Spaces
Crawl space ventilation was meant to keep a constant supply of fresh air circulating throughout the crawl space environment.
It was thought that this would help purge the space of the heavy, damp air that settles in the lower levels of a house.
This belief had become so widespread that crawl space vents were actually written into the International Building Code!
As a result many homes in Georgia, South Carolina and North Carolina have crawl space vents which are counterproductive in keeping your crawl space dry and moisture-free.
In recent years, however, these codes are quickly changing to reflect improvements in the industry and scientific study.
What Crawl Space Humidity Research Says
Consider these crawl space humidity facts:
- Isaac Newton discovered in 1717 that wet air is actually lighter than dry air! It makes a lot of sense - if damp air was heavier, what would clouds be made of? And why would crawl space vents, which are at ground level, ever bring dry air into your home?
- If it's rainy, humid, foggy, or snowing outside, you're bringing wet air into your home.
- Advanced Energy reports that crawl space ventilation brings wet air into your home [PDF] when it's wet outside. Water that is pooling around your vents, will also flow into the space.
- Crawl space moisture helps mold, rot, and mildew grow. This means serious damage for your crawl space!
More science: Hot air rises, leaving your house through the roof and upper levels. This creates a vacuum below that is filled by air from your crawl space, basement, and from outside. Air in your crawl space eventually enters the rest of your home!
Consider These Two Scenarios:
Winter Air - Frigid air fills your crawl space, making the floor above cold. It cools your hot water pipes, your water heater, your furnace, and your heating ducts. Your utilities work harder and cost you more to run, and your home is drafty and uncomfortable.
Summer Air - Hot, humid air enters the crawl space, where the earth cools it naturally. According to Builder Magazine [PDF], this humidity will lead to condensation on your pipes, wood, and cool surfaces, leading to mold and rot. Damp air rises upward into your home. Wet air is harder to cool than dry air, and you spend more on utilities. Meanwhile, your crawl space insulation gets wet, loses its insulative value, grows mold, and drips to the floor. Moist, rotting wood is a perfect place for termites, ants, rodents, and other creatures to move in!
When crawl space insulation is saturated with water, it drips off onto the floor.
Crawl Space Encapsulation
Crawl space ventilation does not work.
If your crawl space is rotting and moldy, then you already know this.
To protect your crawl space, follow these steps:
- Eliminate any flooding with a crawl space sump pump system
- Seal your crawl space vents and doors with airtight covers
- Line your crawl space walls and floors (even if they are concrete) with a thick, durable plastic liner
- Install a self-draining, strong dehumidifier in the crawl space
This keeps everything you don't want in your crawl space outside -- including moisture, cold air, and insects.
Your crawl space will be dry and usable as storage space, and as an added benefit, a crawl space liner will even serve as a passive radon mitigation system!
All-Dry of the Carolinas would like to help you create a dry, healthier crawl space. If you'd like a free, on-site consultation, call or e-mail us today!
We service Georgia, South Carolina and North Carolina, including Elberton, Asheville, Greenville, Rock Hill, Anderson, Clemson, Columbia and nearby areas.
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- Crawl Space
- Foundation Repair
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- Finish your Basement
- Commercial Foundation Repair
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South Carolina Areas
Oconcee County
Fair Play, SC
Long Creek, SC
Mountain Rest, SC
Newry, SC
Richland, SC
Salem, SC
Seneca, SC
Tamassee, SC
Walhalla, SC
West Union, SC
Westminster, SC
Pickens County
Central, SC
Clemson, SC
Easley, SC
Liberty, SC
Norris, SC
Pickens, SC
Six Mile, SC
Sunset, SC
Greenville County
Cleveland, SC
Conestee, SC
Fountain Inn, SC
Greenville, SC
Greer, SC
Marietta, SC
Mauldin, SC
Piedmont, SC
Simpsonville, SC
Slater, SC
Taylors, SC
Tigerville, SC
Travelers Rest, SC
Spartanburg County
Arcadia, SC
Boiling Springs, SC
Campobello, SC
Chesnee, SC
Clifton, SC
Converse, SC
Cowpens,SC
Cross Anchor, SC
Drayton, SC
Duncan, SC
Enoree, SC
Fairforest, SC
Fingerville, SC
Glendale, SC
Gramling, SC
Inman, SC
Landrum, SC
Lyman, SC
Mayo, SC
Moore, SC
Pacolet, SC
Pacolet Mills, SC
Pauline, SC
Reidville, SC
Roebuck, SC
Spartanburg, SC
Startex, SC
Una, SC
Valley Falls, SC
Wellford, SC
White Stone, SC
Woodruff, SC
Cherokee County
Blacksburg, SC
Gaffney, SC
Kings Creek, SC
York County
Bowling Green, SC
Catawba, SC
Clover, SC
Fort Mill, SC
Hickory Grove, SC
Lake Wylie, SC
McConnells, SC
Rock Hill, SC
Sharon, SC
Smyrna, SC
Tega Cay, SC
York, SC
Union County
Buffalo, SC
Carlisle, SC
Jonesville, SC
Lockhart, SC
Union, SC
Laurens County
Clinton, SC
Cross Hill, SC
Gray Court, SC
Joanna, SC
Laurens, SC
Mountville, SC
Waterloo, SC
Lancaster County
Heath Springs, SC
Kershaw, SC
Lancaster, SC
Van Wyck, SC
Fairfield County
Blair, SC
Jenkinsville, SC
Ridgeway, SC
Rion, SC
White Oak, SC
Winnsboro, SC
Edgefield County
Edgefield, SC
Johnston, SC
Trenton, SC
Saluda County
Monetta, SC
Ridge Spring, SC
Saluda, SC
Ward, SC
Aiken County
Aiken, SC
Bath, SC
Beech Island, SC
Clearwater, SC
Gloverville, SC
Graniteville, SC
Jackson, SC
Langley, SC
Montmorenci, SC
New Ellenton, SC
North Augusta, SC
Perry, SC
Salley, SC
Vaucluse, SC
Wagener, SC
Warrenville, SC
Windsor, SC
McCormick County
Clarks Hill, SC
McCormick, SC
Modoc, SC
Mount Carmel, SC
Parksville, SC
Plum Branch, SC
Lexington County
Batesburg, SC
Cayce, SC
Chapin, SC
Gaston, SC
Gilbert, SC
Leesville, SC
Lexington, SC
Pelion, SC
Springdale, SC
Swansea, SC
West Columbia, SC
North Carolina Areas:
Buncombe
Asheville, NC
Black Mountain, NC
Hominy, NC
Leicester, NC
Clay
Shooting Creek, NC
Graham
Cheoah, NC
Robbinsville, NC
Haywood
Canton, NC
Center Pigeon, NC
Clyde, NC
Crabtree, NC
Fines Creek, NC
Ivy Hills, NC
Iron Duff, NC
Lake Junaluska, NC
Maggie Valley, NC
Waynesville, NC
West Canton, NC
Henderson
Crab Creek, NC
Hendersonville, NC
Hoopers Creek, NC
Little River, NC
Mills River, NC
Mountain Home, NC
Valley Hill, NC
Jackson
Cashiers, NC
Tuckasegee, NC
Macon
Elijay, NC
Franklin, NC
Highlands, NC
Norton, NC
Orlando, NC
Scaly Mountain, NC
McDowell
Deer Lick Gap, NC
Glenwood, NC
Marion, NC
North Cove, NC
West Marion, NC
Polk
Columbus, NC
Lynn, NC
Mill Spring, NC
Saluda, NC
Tryon, NC
Rutherford
Gilkey, NC
Lake Lure, NC
Union, NC
Transylvania
Balsam Grove, NC
Brevard, NC
Catheys Creek, NC
Cedar Mountain, NC
Dunns Rock, NC
Lake Toxaway, NC
Little River, NC
Pisgah Forest, NC
Rosman, NC
Yancey
Burnsville, NC
Pensacola, NC
Potato Knob, NC
Price Creek, NC
Georgia Areas:
Banks
Hollingsworth, GA
Elbert
Bowman, GA
Elberton, GA
Montevideo, GA
Franklin
Carnesville, GA
Lavonia, GA
Royston, GA
Unity, GA
Vandiver, GA
Habersham
Baldwin, GA
Clarkesville, GA
Cornelia, GA
Demorest, GA
Mount Airey, GA
Turnerville, GA
Hart
Bowersville, GA
Hartwell, GA
Reed Creek, GA
Madison
Alvin, GA
Bond, GA
Canon, GA
Carlton, GA
Comer, GA
Danielsville, GA
Harrison, GA
Shiloh, GA
Rabun
Clayton, GA
Dillard, GA
Mountain City, GA
Rabun Gap, GA
Sky Valley, GA
Tiger, GA
Stephens
Avalon, GA
Martin, GA
Toccoa, GA
Union Hill, GA
Towns
Titus, GA
White
Helen, GA