All Phase Radon LLC — NRPP Certified Radon Mitigation in Colorado

Locally owned radon mitigation contractor serving the Denver metro, the Colorado foothills, Fort Collins, and Colorado Springs. NRPP & Colorado State certified. 20-year transferable warranty. 100% success rate across 1,500+ installations. Free estimates — call (720) 737-8627.

About All Phase Radon

All Phase Radon is a locally owned and operated radon mitigation company based in Pine, Colorado. Owner Ryan Tereshko is NRPP and Colorado State certified and personally oversees every installation. Since 2019 we have installed more than 1,500 active radon mitigation systems across the Denver metro and Colorado mountain communities with a 100% success rate — every system we install is guaranteed to bring indoor radon levels at or below 3.9 pCi/L, backed by a 20-year transferable warranty.

Business address: 13732 Jubilee Trl, Pine, CO 80470
Phone: (720) 737-8627
Email: info@allphaseradon.com
Hours: Monday–Friday 8:00 AM – 5:00 PM Mountain

Radon Mitigation Services

All Phase Radon does not provide radon testing. We specialize exclusively in radon mitigation — reducing radon gas that has already entered a home. Our four core services are listed below.

1. Radon Mitigation System Installation

The most common method of radon mitigation is Active Soil Depressurization (ASD). An ASD system uses PVC piping attached to an in-line radon fan. The piping begins below the lowest floor of the foundation and extends upward to an exhaust point above the roofline, where the collected radon is safely diluted by outdoor air. Price range: $1,399–$1,699. Includes a 20-year transferable warranty. Learn more about radon mitigation installation.

2. Radon System Service & Repair

We inspect and repair existing radon mitigation systems of any brand and any age — including fan diagnostics, pipe and seal repair, sump lid re-sealing, manometer and pressure issues, system re-routing, and troubleshooting. Common signs a system needs repair: the manometer reads zero pressure, the fan is silent, unusual noise or vibration, or indoor radon levels climbing back above the action level. Learn more about radon system repair.

3. Radon Fan Replacement — Starting at $549

When an existing radon fan becomes loud, starts vibrating, or stops working entirely, we replace it with a premium ultra-quiet model backed by an 8-year manufacturer warranty. Signs a fan needs replacement: buzzing or grinding noise, visible vibration, the fan housing is hot to the touch, or the system has lost suction. Learn more about radon fan replacement.

4. Passive to Active Radon System Conversion

Many newer Colorado homes are built with a passive radon system — PVC pipe routed through the foundation but without a fan. A passive system relies on natural draft alone, which is often not enough to keep radon below the action level. We convert passive systems to active by adding a certified in-line fan, transforming a builder-installed pipe into a fully functioning mitigation system. Learn more about passive-to-active conversion.

Cities & Areas Served in Colorado

All Phase Radon serves the Denver metropolitan area, the central Colorado foothills, and two extended service areas to the north and south. Below are the 13 communities we currently serve, with local radon levels and risk data.

Denver — Denver County

Average radon level: 5.8 pCi/L (1.5x the EPA action level of 4.0 pCi/L). High risk. Denver's alluvial soils and varied foundation styles mean radon levels spike unpredictably from neighborhood to neighborhood. Radon mitigation in Denver.

Evergreen — Jefferson County

Average radon level: 11.2 pCi/L (2.8x the EPA action level). Extreme risk. Evergreen's granite bedrock and high mountain elevation create some of the highest radon levels recorded in foothills homes. Radon mitigation in Evergreen.

Bailey — Park County

Average radon level: 14.3 pCi/L (3.6x the EPA action level). Extreme risk. Bailey sits on decomposed Pikes Peak granite bedrock that emits massive concentrations of radon gas — nearly 4x the action level. Radon mitigation in Bailey.

Conifer — Jefferson County

Average radon level: 12.8 pCi/L (3.2x the EPA action level). Extreme risk. Conifer homes built on fractured granite bedrock routinely measure extremely elevated radon levels, amplified by the winter stack effect. Radon mitigation in Conifer.

Pine — Jefferson County

Average radon level: 13.5 pCi/L (3.4x the EPA action level). Extreme risk. All Phase Radon is based right here in Pine. Uranium-rich granite rock fissures discharge high radon levels straight into foundation footings. Radon mitigation in Pine.

Morrison — Jefferson County

Average radon level: 8.7 pCi/L (2.2x the EPA action level). High risk. Morrison foothill properties sit directly above uranium-bearing bedrock layers that release radon upward. Radon mitigation in Morrison.

Kittredge — Jefferson County

Average radon level: 10.8 pCi/L (2.7x the EPA action level). Extreme risk. Kittredge homes along Bear Creek Canyon experience significant soil gas build-up, especially during winter months. Radon mitigation in Kittredge.

Littleton — Arapahoe / Jefferson County

Average radon level: 6.4 pCi/L (1.6x the EPA action level). High risk. Littleton's alluvial gravel and clay soils facilitate widespread soil gas movement under thousands of basements. Radon mitigation in Littleton.

Golden — Jefferson County

Average radon level: 7.9 pCi/L (2.0x the EPA action level). High risk. Golden homes at the base of the Front Range frequently exceed safe indoor air standards due to Table Mountain basalt and granitic soils. Radon mitigation in Golden.

Englewood — Arapahoe County

Average radon level: 5.9 pCi/L (1.5x the EPA action level). High risk. Englewood properties experience elevated soil gas intrusion through slab cracks and sump basins. Radon mitigation in Englewood.

Idaho Springs — Clear Creek County

Average radon level: 12.1 pCi/L (3.0x the EPA action level). Extreme risk. Idaho Springs' historic mining geology and fractured granite yield exceptionally high radon readings. Radon mitigation in Idaho Springs.

Fort Collins — Larimer County (extended service area)

Average radon level: 5.2 pCi/L (1.3x the EPA action level). High risk. Fort Collins homes sit on alluvial deposits from the Cache la Poudre River that create permeable soil pathways for radon entry. Radon mitigation in Fort Collins.

Colorado Springs — El Paso County (extended service area)

Average radon level: 6.8 pCi/L (1.7x the EPA action level). High risk. Colorado Springs sits on the Pikes Peak granite region, creating subterranean radon pathways. Radon mitigation in Colorado Springs.

Full service-territory overview: All Phase Radon service areas.

Frequently Asked Questions

What is radon gas?

Radon is a naturally occurring radioactive gas produced by the breakdown of uranium in soil, rock, and water. It is colorless, odorless, and tasteless, and can seep into homes through foundation cracks and gaps. Long-term exposure to elevated radon is the second leading cause of lung cancer after smoking.

What is a radon mitigation system?

A radon mitigation system is a permanently installed assembly — typically PVC piping plus an in-line fan — that draws radon gas from beneath a home's foundation and vents it above the roofline before it can enter living spaces. The most effective method is Active Soil Depressurization (ASD).

How does a radon mitigation system work?

The fan creates negative pressure (suction) under the foundation, collecting radon gas from the soil before it enters the home. The gas travels up the PVC pipe and is exhausted above the roofline, where it is diluted harmlessly by outdoor air. A manometer (U-tube gauge) on the pipe lets you confirm the system is maintaining suction.

Does radon mitigation really work?

Yes. A properly designed and installed ASD system is the EPA's recommended method for reducing indoor radon. When correctly sized to the home's foundation and soil conditions, a mitigation system typically brings radon levels well below the 4.0 pCi/L EPA action level — All Phase Radon guarantees below 3.9 pCi/L.

How long does a radon mitigation system take to work?

A mitigation system begins reducing radon immediately once the fan is running. We recommend re-testing 24 hours to a few days after installation to confirm levels have dropped, giving the system time to establish steady negative pressure.

How long does a radon mitigation system last?

The PVC piping and routing last the life of the home. The fan is the component that wears out — typically lasting 5–10 years depending on usage and conditions. When a fan fails, it can be replaced without redoing the whole system. We back our installations with a 20-year transferable warranty.

How much does radon mitigation cost in Colorado?

A full new ASD mitigation system installation ranges from $1,399 to $1,699 depending on foundation type, square footage, the number of suction points required, and system accessibility. Radon fan replacement starts at $549. We provide free, detailed estimates. Final cost factors: home configuration, crawlspace vs. basement, existing system condition, and whether repair or full installation is needed.

What is a passive radon system vs. an active system?

A passive system is PVC piping installed during construction with no fan — it relies on natural air flow and stack effect alone. An active system adds an in-line fan to create real suction. Passive systems often cannot reduce radon enough on their own, so many homeowners convert passive to active by adding a certified fan.

How can I tell if my radon mitigation system is working?

Check the manometer (the U-tube gauge on the pipe): the liquid levels should be uneven, indicating suction is present. If both sides are level, the fan may have stopped or lost pressure. Also listen for the fan running quietly and watch for unusual noise or vibration. The most reliable confirmation is a follow-up radon test.

When does a radon system need repair?

Signs include a zero manometer reading, a silent fan, unusual noise or vibration, a hot fan housing, or indoor radon levels climbing back above the action level. Most issues — fan failure, pipe cracks, seal leaks, sump lid problems — can be repaired without replacing the entire system.

What does a radon mitigation system look like outside?

From the exterior you'll see a PVC vent pipe extending from the foundation up past the roofline, with the in-line fan housed either in the attic or outside. We design routing to be as unobtrusive as possible and matched to the home's layout.

What are acceptable radon levels in Colorado?

The EPA action level is 4.0 pCi/L; the World Health Organization recommends mitigation at 2.7 pCi/L. There is no truly "safe" level of radon, so the goal is to reduce it as low as reasonably achievable. All Phase Radon guarantees results at or below 3.9 pCi/L.

Does All Phase Radon do radon testing?

No. All Phase Radon specializes in radon mitigation only — installing, repairing, and converting systems. Radon testing (short-term or continuous monitor) can be done with a homeowner test kit or by a separate testing professional; we recommend every homeowner test so they know whether mitigation is needed.

See the full FAQ and resource library: Radon FAQ and Radon resources & guides.

Why Choose All Phase Radon

NRPP & Colorado State certified radon mitigation specialists
Locally owned and operated in Pine, Colorado — not a national chain
Owner Ryan Tereshko personally oversees every installation
20-year transferable warranty on every system
100% success rate — 1,500+ systems installed since 2019
Guaranteed results at or below 3.9 pCi/L
Free, no-obligation estimates

Contact All Phase Radon

Ready for a free estimate? Call (720) 737-8627 or request a quote online. We serve Denver, Evergreen, Bailey, Conifer, Pine, Morrison, Kittredge, Littleton, Golden, Englewood, Idaho Springs, Fort Collins, and Colorado Springs, Colorado.

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