What is the SCV System?
The SCV System™ (Soil Contaminant Ventilation) is a proprietary system developed by Healthy Home Restoration that manages soil-based contaminants beneath the sealed vapor barrier of an encapsulated crawlspace. It creates controlled negative pressure under the liner to prevent long-term migration of microbial gases and contaminants into the crawlspace air.
Why isn’t a sealed vapor barrier enough?
A vapor barrier controls moisture vapor coming from the soil, but it does not permanently eliminate soil gases or microbial activity beneath the liner. Over time, gases and microscopic contaminants can accumulate and migrate upward through seams, penetrations, and porous masonry materials unless sub-barrier pressure is controlled.
Does every encapsulated crawlspace need soil contaminant ventilation?
If the goal is simply moisture control, traditional encapsulation may appear sufficient.
If the goal is long-term indoor air quality improvement, managing what happens beneath the vapor barrier becomes critically important.
Is this about radon?
While radon does increase in virtually all sealed crawlspaces, the SCV System was developed primarily to manage soil-based microbial contaminants such as mold byproducts, fungal gases, bacteria, and yeast. Radon is only one example of how soil gases behave when a crawlspace is sealedand yes, The SCV system will remediate radon gases and in most cases, better than a traditional radon remediation can do.
Can I add a radon remediation system to my existing encapsulation?
This is actually a common problem and it goes like this:
Someone converts their crawlspace into a new sealed crawlspace and then later finds out that the radon levels in the home are a problem. At that point, a traditional radon remediation company is called and then the new problems begin! To start, radon companies business model has focused on homes with a basement or concrete slab as radon has never really been an issue in most homes with the traditionally ventilated crawlspaces so this new industry is something they are not trained on and definitely do not understand. Most radon system will pull way to much air out from under the vapor barrier using the same blowers that were designed to pull air out from under a concrete slab where the vacuum pressure is much greater! Now the high negate pressure ventilation will become a problem with things like:
- Higher seasonal indoor humidity. These issues start during the heat of the summer the damp fall seasons and can even cause mold growth indoors.
- The high volume of negative air can also cause the dehumidifier under the home to work much harder and this can not only shorten the life of that dehumidifier but it will drive up the energy cost.
The SCV System was designed as a perfect marriage between the encapsulation industry and the radon industry to avoid these problems that are becoming an issue throughout the area.
Why don’t other contractors offer this?
The main reason… the industry does not even know it is an issue and certainly do not understand it. Most encapsulation systems were designed to control humidity and visible mold growth on framing materials. The concept of sub-barrier soil negative air ventilation is not part of the conversation and there is no training, no certifications, basically nothing that an industry focused on dry air would be aware of. At HHR (HEALTHY Home Restoration) this IS our focus. The SCV System was developed through long-term field research specifically to address that gap.
How do I know if this matters for my home?
If you are encapsulating your crawlspace to improve indoor air quality, not just to reduce humidity, then it matters and is extremely important to understand.
