
Crawl Space Encapsulation
Crawl space encapsulation may be one of the most debated and confusing topics within residential building construction. Everywhere you look, you can find another opinion, another study, or another warning. Therefore, a large part of this confusion is that crawl space encapsulation means many different things to many different contractors who all claim to be experts in this field. There are so many variations in encapsulations also referred to as closed or unvented crawl spaces.

Examples of variation within crawl space encapsulation:
- Insulation in the foundation ceiling
- Insulation on the perimeter walls
- Vapor barrier only on ground
- Vapor barrier fully taped and sealed and up the walls and piers
- Thickness and quality of vapor barrier materials
- Exterior waterproofing that has occurred
- Proper interior waterproofing and drainage through sump pumps or French drains
- No drying mechanism installed – just closed vents
- Drying with use of dehumidifier
- Drying with use of conditioned air from the living space
- Exhaust vent fans to outside
- Return air to living space
Is your head spinning yet? As you can see, there are many different methods to crawl space encapsulation. There are pros and cons to these different and combined approaches. Furthermore, every crawl space has different characteristics due to geography or construction. There isn’t a simple one size fits all.
Goals of crawl space encapsulation
There are different goals to crawl space encapsulation. Some are trying to make the house more energy efficient overall, and others are trying to reduce moisture in the crawl space by limiting ground moisture and limiting outside air. Benefits to different methods get “muddy” to say the least when we pick and choose only certain aspects of the overall crawl space encapsulation. There are many companies touting benefits yet also cutting corners. A closed crawl space can be an effective way to control moisture, but it isn’t simple and there are many things that need to be done correctly. Work with a reputable installer as you evaluate your options to avoid unintended problems in your crawl space.
ATMOX Products Improve Any Crawl Space

ATMOX products are designed with fully-automated technology to enhance and improve any crawl space. The goal of the crawl space ATMOXsphere is always moisture reduction, energy efficiency and air quality. These are the guiding principles in all product development. Whether your crawl space is a traditionally vented space or an encapsulated crawl space, ATMOX products should be considered as part of your overall solution.
Moisture Control
The core product is the ATMOX controller. The controller works using sensors and sophisticated software programmed to operate selected components. Specifically, this controller uses highly accurate sensors to measure information on temperature, dew point and humidity in your crawl space. Controlling moisture levels in your crawl space is important for maintaining a healthy and safe environment that promotes good air quality throughout your home.
Dehumidification
Most dehumidifiers have a relative humidity sensor within the unit to direct it to turn on and off based on humidity levels above set point. With the ATMOX controller, the operation will be determined based on the ATMOX inside sensor which will be placed in a more central or neutral location away from the unit itself. The area directly around the dehumidifier is often the most dry and not always representative of the entire crawl space. Also, the ATMOX controller will ensure that the dehumidifier is only running within its operational temperature range.

In a crawl space (especially when it has a low height), a dehumidifier struggles to dry the air in the space evenly. Furthermore, the dehumidifiers have a tendency to dry the areas near the dehumidifier very well or almost too much. At the same time, far reaching corners of the crawl space may not be getting the beneficial air exchanges to and from the dehumidifier. The ATMOX circulation fans greatly enhance the effectiveness and range of the dehumidifier.
Air Quality
A key component to air quality is fresh outside air. This only happens by exchanging the air in the crawl space to keep it from getting stagnant. Closed crawl spaces often suffer from odor buildups from either soil gasses or other materials. With no ventilation to the outside, these odors creep up into the living space.
The ATMOX controller has an optional setting to intentionally run fans with outside air periodically. Unlike other fan setups, it is not a simple timer. Specifically, the forced ventilation setting will incorporate minimum temperatures, duration and run times since last operation.

In the complex world of crawl space encapsulation, where opinions and methods vary widely, it’s easy to become overwhelmed by the multitude of choices and considerations. Furthermore, encapsulation means different things to different contractors, and the numerous variations in approaches can make your research more confusing. ATMOX products enhance the overall effectiveness of your crawl space moisture solution, addressing the challenges of moisture control and air quality and ensuring that the crawl space remains a healthy part of the home.