Crawl Space Repair in CO & NM, including Canon City, Durango & Grand Junction.

Crawl Space Ventilation in Colorado & New Mexico

How Crawl Space Vents Affect Crawl Space Humidity... And Why

Grated Crawl Space Vents outside a home in Alamosa

Crawl space vents can usually keep out mice and rodents, but what about termites, carpenter ants, and other insects?

Crawl Space ventilation is the answer that contractors have historically given to the issue of crawl space humidity in homes.

Generally, this 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 -- usually a wooden/metal grating, or a mesh covering.

The covering is installed to prevent infestations from rodents and animals, but they cannot prevent insects such as termites and carpenter ants.

crawl space ventilation and air movement in a building

Crawl space ventilation moves outside air through the house. This affects utility bills and, when that air holds mold spores, your 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 to purge the space of the heavy, damp air in the house that settles in the lower levels.

Additionally, some contractors claim that damp, humid air is heavier than dry air, causing all the moisture in the home to sink down into the crawl space.

This belief had become so widespread that crawl space vents were actually written into the International Building Code!

In recent years, however, these codes are quickly changing to reflect improvements in the industry and formal scientific study.

Engineers and building scientists are becoming more and more aware of how crawl space humidity really works in a home, and are taking steps to stop the practice of venting crawl space environments.

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 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!

Here's a little 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 crawlspace, 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, 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!

mold crawl space insulation dripping off the floor joist

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:

  1. Eliminate any flooding with a crawl space sump pump system
  2. Seal your crawl space vents and doors with airtight covers.
  3. Line your crawl space walls and floors (even if they are concrete) with a thick, durable plastic liner
  4. 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, termites, and ants.

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!

Silver River Basement Systems 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 Colorado & New Mexico, including Greater Grand Junction. More information about Crawl Space Vapor Barriers.

Looking for a price? Get a no cost, no obligation free estimate.

Serving CO & NM including the Greater Grand Junction area
Our Colorado & New Mexico Service Area
Cities in Alamosa County, CO
Alamosa
Hooper
Mosca

Cities in Archuleta County, CO
Arboles
Chromo
Pagosa Springs

Cities in Conejos County, CO
Antonito
Capulin
Conejos
La Jara
Manassa
Romeo
Sanford

Cities in Custer County, CO
Westcliffe
Wetmore

Cities in Delta County, CO
Austin
Cedaredge
Cory
Crawford
Delta
Eckert
Hotchkiss
Lazear
Paonia

Cities in Dolores County, CO
Cahone
Dove Creek
Rico

Cities in Fremont County, CO
Canon City
Coal Creek
Coaldale
Cotopaxi
Florence
Hillside
Howard
Penrose
Rockvale

Cities in Gunnison County, CO
Almont
Crested Butte
Gunnison
Ohio City
Parlin
Pitkin
Powderhorn
Somerset

Cities in Hinsdale County, CO
Lake City

Cities in La Plata County, CO
Bayfield
Durango

Cities in Mesa County, CO
Clifton
Collbran
De Beque
Fruita
Gateway
Glade Park
Grand Junction
Loma
Mack
Mesa
Molina
Palisade
Whitewater

Cities in Mineral County, CO
Creede

Cities in Montezuma County, CO
Cortez
Dolores
Lewis
Mancos
Mesa Verde National Park
Pleasant View
Towaoc
Yellow Jacket

Cities in Montrose County, CO
Bedrock
Cimarron
Montrose
Naturita
Nucla
Olathe
Paradox
Redvale

Cities in Ouray County, CO
Ouray
Ridgway

Cities in Rio Grande County, CO
Center

Cities in Saguache County, CO
Crestone
Moffat
Saguache
Sargents
Villa Grove

Cities in San Juan County, CO
Silverton

Cities in San Miguel County, CO
Egnar
Norwood
Ophir
Placerville
Telluride

Cities in Rio Arriba County, NM
Abiquiu
Alcalde
Canjilon
Canones
Cebolla
Chama
Chimayo
Cordova
Coyote
Dixon
Dulce
El Rito
Embudo
Espanola
Gallina
Hernandez
La Madera
Lindrith
Los Ojos
Medanales
Petaca
Tierra Amarilla
Truchas
Vallecitos
Velarde
Youngsville

Cities in San Juan County, NM
Aztec
Blanco
Bloomfield
Farmington
Flora Vista
Fruitland
Kirtland
La Plata
Nageezi
Navajo Dam
Newcomb
Sanostee
Sheep Springs
Shiprock
Waterflow

Our Locations:

Silver River Basement Systems
P.O. Box 905
Ship:1871 North Hwy. 149
Lake City, CO 81235
1-970-238-8873