. Moisture
Whether it's from standing water after a rainstorm or just the dirt floor, evaporating moisture can damage wood and insulation and eventually make its way into your home. Mold in the crawl space and upstairs living areas is a common problem caused by excess moisture.
Pests (and their droppings)
Moisture in the crawl space is a magnet for spiders, mice, rats, snakes, termites and other nasty pests. Because the crawl space is usually left undisturbed, this provides a safe haven for critters looking for a cozy home. What's more, much like our kids, critters don't usually clean up after themselves. Pathogens from rodent droppings ad urine can affect the air quality inside your home.
. Radon
You can't see or smell radon gas, but it's found in almost all soils. It comes from the natural decay of uranium and it moves up through the ground and into the air above and eventually into your home.
Outside air
If the air outside is worse than the air inside, then vents into the crawl space will let this polluted outside air into your crawl space and eventually up into your home. The poor air quality can make allergies, asthma and respiratory issues worse.
Drainage Matting
Drainage mats come with a dimpled design that lets water accumulate and flow away, creating an air gap.
. Ducts in the crawl space
If the ducting for your HVAC system is running through the crawl space, it acts as a highway, carrying all the dust, moisture, rodent droppings, and chemicals from the crawl space directly into your living space and your air.
