A complete system with every one of the above components allows any soil gases - including radon gas - that naturally occur underneath the liner system, to wick through the drain fabric and escape out through the ventilation pipe. While improved indoor quality of air is the principal advantageous asset of a sealed and insulated crawl space, the homeowner may also appreciate a brilliant, clean, and dry storage space; the ridding of musty smells; less energy usage; and tax credits. Contractors encapsulating crawl spaces will have more to provide with their clients when they are able to assure the peace of mind with improved indoor air quality.
Crawl spaces are inherently dirty smelly places that will contain all types of unwanted odors from mold & mildew to urine & feces. Some aspects of the nation may also have soil underneath your home with odorless, harmful gases like radon gas. I'm a huge believer that the most effective long-term solution to solve these problems is to encapsulate the air underneath your home with a liner system. It is really a inherently impossible to keep rodents, bugs and mold from the area underneath the house since the soil is exposed - but it's relatively simple to create a barrier between the house and crawl space the keep out each one of these unwanted nuisances.
I had a good lady write me last week telling me relating to this house she'd just purchased that formerly had many cats living in the crawl space and they left out the smell of a giant litter box underneath her home. The odors were coming up through the wooden floor and creating a very fowl smell in the house. She explained she tried many different solutions: spreading baking soda, spraying a molecule treatment originally meant for carpets & laying down new top soil - obviously none worked
https://trans4mind.com/counterpoint/index-home-garden/common-crawl-space-problems.html .
I wrote her back, apologized on her behalf wasted time and suggested that she treat her crawl space such as a wild beast that you can't defeat, only contain. She took my advise, installed a crawl space encapsulation system and the smells immediately went away.Encapsulation systems are rated by permeability - 0.000 is the best, normal plastic is 0.01 and wood is 0.2. To avoid all smells, moisture and gases try to find an encapsulation liner system with a 0.000 permeability rating. A zero perm liner will even completely weatherize the crawl space and save on energy bills since the outside air won't be able to leak to the home.