Did You Know That?
20+ Interesting Crawl Space Facts
by Tim Wilkerson
- An un-insulated crawl space can account for up to 20% of your home’s heating cost. 
- Insulating the crawl space floor joist does little good (cold air is sucked right up through it – due to what the US E.P.A. has coined “The Stack Effect”). 
- A 1,000 sq. ft. dirt/stone crawl space can let in up to 15 gallons of water in the form of water vapor each day. 
- The world health organization blames crawl spaces for a myriad of health problems. 
- There are three modes of heat transfer: conduction, convection and radiation (radiant heat). 
- Radiant heat transfer is the primary mode of heat loss in your home. 
- Gold, silver and aluminum reflect radiant heat. 
- Aluminum foil has been used throughout Europe to reduce Energy Cost for decades. 
- Excessive moisture can cause serious structural damage to your home’s Foundation. 
- Mold can cause illnesses in humans ranging form headaches and fatigue to brain damage and death. 
- Moisture always moves from wet to dry. 
- Heat transfer always occurs from hot to cold. 
- Mold is not harmful unless its spores become air borne. 
- Mold cannot grow/reproduce/release its spores into the air if humidity levels are bellow 50%, or there is sufficient moisture at its food source, such as wet wood. 
- Mold needs moisture, food (organic material) and oxygen to survive. 
- That musty odor you smell is the gases that molds release into the air as they feed and grow – not the mold spores, a common misconception. 
- Like mold, dust mites need moisture to survive. 
- Dust mites do not drink water; they absorb it form the air. 
- An 8 in. thick concrete foundation wall has less than 1-R. value (almost no insulating value). 
- Warm air holds more moisture than cold air. 
- The dew point is equal to the temperature at which air can no longer hold its moisture, thus condensation or water droplets are formed (i.e. sweating pipes in a damp crawl space). 
- Radon gas is the number two cause of lung cancer – second only to smoking. 
- As much as 50% of the air you breath in your home comes from your crawl space. 
