Passive Radon System Activation in Colorado
A passive radon system is designed to reduce radon by allowing soil gases to move through a vent pipe without mechanical assistance. If the system is not reducing radon levels enough, it may be possible to activate it by adding mechanical ventilation and converting it into an active radon mitigation system. Colorado Radon Mitigation can evaluate an existing passive system and help determine the appropriate next step.
What Is a Passive Radon System?
A passive radon system is a radon-reduction system that relies on natural air movement rather than a powered fan. These systems are commonly installed during radon-resistant new construction in both residential and commercial properties and are intended to help move radon and other soil gases from beneath the building to the outdoors.
A passive system may include a vent pipe extending from beneath the foundation and terminating above the roofline. Because there is no powered fan creating continuous suction, performance can vary depending on the property, construction details, pressure conditions, and radon levels.
If testing shows that radon remains elevated, the passive system may need to be evaluated for activation.
Colorado Radon Mitigation evaluates builder-installed passive systems before activation because construction details can vary significantly. A passive vent being present does not necessarily mean the original system was installed correctly or is ready for straightforward activation.
What Does Passive Radon System Activation Mean?
Passive radon system activation generally means converting an existing passive system into an active radon mitigation system by adding mechanical suction.
The goal is to create more consistent negative pressure beneath the foundation so radon gas is actively drawn from the soil and vented safely outside rather than relying only on natural airflow.
Whether an existing passive system can be activated depends on how the system was originally installed and the conditions of the property.
When the existing passive system is suitable for activation, Colorado Radon Mitigation installs a radon fan selected for the property and system conditions. The activated system also includes a visual manometer and an audible system alarm. After the fan is operating, the team performs Pressure Field Evaluation (PFE) to evaluate whether the system is creating the intended pressure beneath the building.
Our Passive Radon System Activation Process
We follow a thorough, standardized process to ensure reliable results, so you can make confident decisions about your property.
Review the Existing System
We begin by evaluating the passive radon system and how it is currently configured. Colorado Radon Mitigation inspects the vent piping, slab penetration, sub-slab connections, and available power supply before activation.
The system configuration is reviewed to identify installation conditions that could prevent the existing passive system from functioning effectively once a fan is added.
Review Radon Levels
Current radon measurements help determine whether the passive system is adequately reducing indoor radon levels or whether additional mitigation may be needed.
If current radon levels are unknown, radon measurement can help determine whether the existing passive system is adequately reducing indoor radon.
DETERMINE WHETHER ACTIVATION IS APPROPRIATE
The existing system is evaluated to determine whether it can be converted into an active radon mitigation system or whether additional modifications may be necessary.
Straightforward activation may not be possible when the original system uses improper piping materials, lacks an adequate sub-slab suction area, is not connected to drain tile or gas mat, contains excessive fittings or changes in direction, or does not have a suitable power supply near the passive vent piping.
Activate and Evaluate the System
If activation is appropriate, the system is modified to create active suction. After the fan is installed, Colorado Radon Mitigation checks system pressure, completes Pressure Field Evaluation, and verifies the operating components.
Post-mitigation radon testing is also offered because measuring the radon level after activation is the only way to verify how effectively the completed system is reducing indoor radon.
Why Choose Colorado Radon Mitigation?
Local Colorado Knowledge
Radon is a significant concern for Colorado property owners, and system performance can vary by property. Working with a local radon professional helps ensure the system is evaluated in the context of the building and its actual radon measurements, including for property owners looking for radon services in Arvada.
All of our technicians and management are NRPP-certified and Colorado DORA-licensed in both radon measurement and mitigation. The professionals conducting your assessment, preparing your quote, testing your property, and installing your system are individually licensed and certified.
Colorado Radon Mitigation maintains company and individual memberships with the Indoor Environments Association (IEA).
Experience With Radon Systems
Colorado Radon Mitigation works with radon testing, measurement, mitigation, and radon-related systems, allowing the team to evaluate activation within the larger context of the property.
Existing-System Evaluation
Activation should not simply mean adding a fan without first evaluating the existing system. The system configuration and current radon levels should help guide the recommendation.
Related Mitigation Support
If an existing passive system cannot be activated as-is, Colorado Radon Mitigation also provides residential radon mitigation and can help determine whether a different solution should be considered. Colorado Radon Mitigation holds NRPP and Colorado DORA credentials for radon mitigation and measurement. The fan installed during passive-system activation includes a 7-year warranty. Because Colorado Radon Mitigation did not install the original passive system, the warranty applies to the new fan rather than the builder-installed system as a whole.
Passive vs. Active Radon Systems
A passive radon system and an active radon mitigation system use similar pathways to move radon from beneath a building, but the main difference is how airflow is created.
Passive Radon System
A passive system relies on natural pressure differences and airflow through the vent piping.
Active Radon System
An active system uses a powered fan to create continuous suction beneath the foundation and move soil gases through the vent system.
For some properties, the passive system may reduce radon adequately. In others, activation may be necessary to improve performance.
The appropriate approach should be based on actual radon measurements and the condition of the existing system rather than assumptions about how the system is performing.
When Should a Passive Radon System Be Activated?
Activation may be appropriate when radon testing shows that an existing passive system is not keeping indoor radon levels sufficiently low.
Situations that may prompt an evaluation include:
- Elevated radon readings despite an existing passive system
- A newly purchased home with a passive radon system already installed
- A home built with radon-resistant construction features but no active fan
- Changes to the home that may affect pressure conditions
- Uncertainty about whether the passive system is functioning effectively
The presence of a passive radon system does not by itself confirm that indoor radon levels are low. Measurement is still necessary to understand actual radon conditions. If you do not have a current result, professional radon testing can establish whether the existing passive system is controlling indoor radon adequately.
Can Every Passive Radon System Be Converted to Active?
Not necessarily.
Some passive systems may already have the venting and sub-slab pathway needed for activation, while others may require modifications. The original installation quality, pipe routing, foundation design, suction potential, and current radon levels can all affect what is needed.
A professional evaluation is the safest way to determine whether simple activation is appropriate or whether the property needs a more complete mitigation solution.
Common problems include missing or inadequate gravel beneath the slab, missing vapor barriers, vent piping that is not connected to sub-slab drain tile or gas mat, inadequate space beneath the slab for an effective suction point, improper piping materials such as ABS, excessive fittings or bends that restrict airflow, and missing or unsuitable electrical service near the passive vent piping.
Passive Radon System Activation FAQs
What is the difference between a passive and active radon system?
A passive radon system relies on natural airflow through vent piping, while an active radon system uses a powered fan to create continuous suction beneath the building. Active systems generally create more consistent airflow.
Can a passive radon system be converted to active?
In many cases, an existing passive system may be able to be converted into an active system, but the existing installation should first be evaluated to determine whether activation is appropriate.
How do you activate a passive radon system?
When the existing system is suitable for activation, Colorado Radon Mitigation installs a radon fan selected for the property and system conditions, adds a visual manometer and audible system alarm, and performs Pressure Field Evaluation to evaluate system performance.
Does activating a passive radon system require replacing the existing system?
Not always. In some cases, the existing venting may be usable and only certain components may need to be added or modified. The system should be evaluated before determining the scope of work.
Should radon levels be tested again after activation?
Yes. Colorado Radon Mitigation recommends post-mitigation testing to verify the radon level after the system has been activated. Professional CRM testing is available, and a home test kit may also be provided as a non-certified testing option.
Find Out if Your Passive Radon System Needs Activation
If your home already has a passive radon system but radon levels remain elevated, the next step may be activation or further system evaluation. Colorado Radon Mitigation can review the existing setup and help determine the appropriate approach.
Ask about our military, veteran, law enforcement, and first responder discounts. Interest-free and low-interest financing options may also be available. Ask us about current terms and eligibility.
Depending on your property and radon concerns, you may also need additional services such as residential radon mitigation, crawl space encapsulation, or radon in water testing. Colorado Radon Mitigation can help determine which services are relevant based on the property and testing results.