Radon Mitigation in Ault, Colorado | InspectandTest
When a radon test in Ault comes back at or above the EPA action level of 4 pCi/L, the next step is mitigation: a permanent system that vents soil gas to the outdoors before it can build up inside the home. Ault, the small farming and railroad town on the northern Weld County plains, sits in EPA Radon Zone 1, the agency’s highest-risk category, so elevated readings are common in the town’s older grain-elevator-era cottages and newer infill builds alike. Radon is a colorless, odorless radioactive gas and the second-leading cause of lung cancer after smoking, which is why a documented fix matters. This page explains how radon mitigation ault homeowners should approach the work, what the systems involve, and what they cost. This summary reflects EPA and CDPHE guidance current as of 2026; consult a certified mitigation professional for your home.
Part of our Radon Mitigation Systems guide — start there for the full picture →
Radon mitigation in Ault: what to know
Radon mitigation is the engineering side of the radon problem. Where testing tells you the number, mitigation lowers it, usually by installing an active sub-slab depressurization system that draws soil gas from beneath the foundation and exhausts it above the roofline. A correctly designed system routinely brings a home from well above 4 pCi/L down to 2 pCi/L or lower. If you have not yet measured your home, start with our guide to radon testing in Ault before committing to a fix.
The principle is simple: a sealed fan creates suction under the slab so radon flows into a pipe rather than into living space. For the broader science and the range of system types, our plain-language radon guide for Front Range homeowners explains the underlying physics and the device options.
Mitigation is a permanent improvement, not a one-time service. The fan runs continuously and the system stays with the house, so a post-mitigation test confirms the fix worked and a periodic re-test confirms it keeps working. EPA guidance is to re-test every couple of years even after a system is installed, because a tripped fan, a cracked pipe, or a new foundation crack can let levels creep back up.
Why Ault homes need radon mitigation
The same plains geology that produces high test results makes mitigation necessary. Weld County’s deep agricultural soils, sitting on the uranium-bearing formations of the DJ Basin oil-and-gas country, release radon steadily, and the flat ground means most Ault homes sit directly on or just above soil that is generating the gas. A high reading here is not a fluke; it reflects the ground the town is built on.
Housing style shapes the fix. Ault’s older cottages from the grain-elevator era often have stone, block, or partial-basement foundations with dirt floors and unsealed crawl spaces that breathe radon directly, while newer slab-on-grade builds are tight enough to trap whatever enters. The long, sealed plains winter, when furnaces run for months and pull a slight negative pressure on the house, is exactly when radon concentrates indoors. An evaporative cooler may mask the problem in summer, but the winter-sealed condition is the one a mitigation system is sized for.
Because many Ault parcels are rural with basements or ground-floor living space directly over soil, the lowest level is frequently occupied, which is the worst case for exposure. Mitigation moves the soil gas out before it reaches that occupied space, which is why a permanent system rather than repeated testing is the answer once a home reads above the action level.
What a radon mitigation system covers
The standard fix for an Ault home is active sub-slab depressurization. A technician cores a hole through the slab, runs PVC pipe from a suction point under the foundation up through the home or along an exterior wall, and installs an inline fan that exhausts the gas above the roofline where it disperses harmlessly.
Sub-slab depressurization
The fan creates a low-pressure field under the entire slab so that soil gas is drawn into the pipe instead of seeping through cracks and joints into living space. Sealing visible slab cracks, the sump cover, and utility penetrations improves the suction field and lets the fan work efficiently. A manometer, a simple U-tube pressure gauge, mounts on the pipe so the homeowner can see at a glance that the system is running.
Crawl spaces and older foundations
Many of Ault’s older homes have crawl spaces or partial dirt-floor basements rather than a full poured slab. For those, the technician installs a sealed membrane over the soil and depressurizes beneath it, effectively turning a leaky crawl space into a sealed surface the fan can draw on. Stone and block foundations common in century-old farm cottages may need extra sealing, since they are inherently more porous than poured concrete.
Radon mitigation cost in Ault
A typical residential radon mitigation system in the Greeley and Weld County market runs about $1,200 to $2,500, with most straightforward installations landing near $1,500. The price depends on the foundation type, the routing of the pipe, and whether a crawl-space membrane is needed. The older, multi-foundation farm homes around Ault sometimes cost more because they combine a basement, a crawl space, and an addition that each need attention.
Against that cost, the benefit is substantial. A system that takes a home from 8 pCi/L to under 2 pCi/L cuts radon exposure by roughly 90 percent for as long as the family lives there. The EPA ties thousands of lung-cancer deaths a year to radon, and in Zone 1 Ault the exposure risk is among the highest in the state, so the one-time cost buys a permanent reduction in a genuine health hazard.
Operating cost is modest: the continuous fan adds a few dollars a month to the electric bill, and a quality fan lasts years before replacement. Compared with the value of the reduction, the ongoing cost is negligible, which is part of why mitigation is the standard response to a high reading rather than living with the gas.
It also helps to see mitigation as a one-time capital improvement that travels with the home rather than a recurring service. Unlike repairs that must be redone, a properly installed system keeps working for years with only a glance at the manometer and an occasional fan replacement. For a family settling into an Ault home for the long haul, that durability makes the upfront cost easier to justify against decades of reduced exposure.
Colorado regulations and disclosure
Colorado requires radon disclosure in residential real-estate transactions, and the Seller’s Property Disclosure asks sellers to report known radon results and any existing mitigation system. A documented, professionally installed system is therefore an asset at sale: it answers the buyer’s radon question before it is asked. CDPHE runs the state radon program and references the 4 pCi/L EPA action level. Colorado does not license home inspectors or mitigators in the way some states do, so confirm your installer follows recognized national standards such as those maintained by AARST and the EPA.
For homes within the broader county, the radon picture is consistent, which our Weld County radon testing hub documents. A buyer who sees a mitigation system with a current post-install test and a working manometer has real reassurance, while a seller who installs one proactively often smooths the transaction and avoids a last-minute credit negotiation.
Neighborhoods and areas served
Mitigation needs turn up across Ault: the older cottages near the historic grain-elevator core, the newer infill and edge-of-town builds, and the rural well-and-septic parcels on the surrounding farmland where basements sit directly over plains soil. Service typically extends to adjacent Eaton, Pierce, Nunn, and nearby Greeley, all within the same Zone 1 footprint. Homeowners comparing nearby options can also review our radon mitigation in Eaton page.
Because the plains geology is consistent across this corner of Weld County, a home that tests high in town and one on a rural acreage face the same uranium-bearing soil and the same fix. The age and foundation type of the individual house, not the neighborhood, determine how the system is designed, which is why a site visit precedes any firm quote.
Living with a mitigation system on the plains
Once a system is installed in an Ault home, the homeowner’s job is mostly to keep an eye on it. The manometer mounted on the pipe is the simplest health check: the two columns of fluid should sit at different levels, showing the fan is pulling suction. If they ever equalize, the fan has likely failed or the pipe has a blockage, and the system needs service before radon levels can climb back up. A glance at the manometer every month or two is enough to catch a problem early.
The plains climate puts a few specific stresses on a system. Hard freezes can affect the exhaust point, and wind-driven snow or debris can occasionally interfere with the discharge, so a routing that exits well above the roofline and away from windows is worth confirming at installation. The fan itself is rated for continuous outdoor or attic operation and typically lasts many years, but it is a mechanical part that will eventually need replacement, usually a straightforward swap for an installer.
Seasonal habits matter too. Many Ault homes run evaporative coolers in summer, which change the home’s air pressure and airflow. A mitigation system is designed to work regardless, but a homeowner who notices the manometer reading shift when the cooler runs should mention it to the installer rather than assume something is wrong. The system is sized for the sealed winter condition, which is when radon exposure is highest, so a stable winter reading below the action level is the real measure of success.
Finally, keep the paperwork. The original test, the post-mitigation test, the system specifications, and any service records form a package that reassures a future buyer and satisfies Colorado disclosure. In a stable farm town where families stay in homes for decades, that documentation also helps the current owner remember when the fan was last checked and when a re-test is due.
How to choose an Ault radon mitigation provider
Ask whether the installer follows EPA and AARST mitigation standards and whether they include a post-mitigation test to confirm the system brought the home below 4 pCi/L. A reputable mitigator guarantees a result, not just an installation, and mounts a visible manometer so you can verify the fan is working. Get the suction point, fan model, and exhaust routing in writing.
For the older multi-foundation farm homes common around Ault, ask specifically how the installer will handle a crawl space or a stone foundation, since those require membrane work and extra sealing that a slab-only quote may not cover. A careful provider inspects the foundation before quoting rather than pricing a generic system sight unseen.
Confirm the installer will re-test after the work and provide the documentation a future buyer will want. Pairing mitigation with a fresh radon test, and ideally a broader inspection of the older structure, gives you one coordinated picture of both the soil-gas fix and the home’s condition. That combination is worth more at resale than a bare system with no paperwork.
References
- Consumer’s guide to radon reduction — U.S. Environmental Protection Agency
- Colorado radon program — Colorado Department of Public Health and Environment
- Radon and lung cancer — Centers for Disease Control and Prevention
Frequently asked questions
When does an Ault home need radon mitigation?
When a test reads at or above the EPA action level of 4 pCi/L. Because Ault sits in Zone 1, elevated readings are common, and mitigation is the standard permanent fix.
How much does radon mitigation cost in Ault?
A typical system runs about $1,200 to $2,500, with most straightforward installations near $1,500. Older multi-foundation farm homes with a crawl space can cost more.
How does a radon mitigation system work?
An active sub-slab depressurization system uses a sealed fan to draw soil gas from beneath the foundation and vent it above the roofline, before it can enter living space.
Do older Ault farmhouses need a special system?
Often yes. Stone or block foundations and dirt-floor crawl spaces need a sealed membrane and extra sealing so the fan can build suction, which a slab-only quote may not include.
Does a mitigation system need re-testing?
Yes. EPA recommends a post-install test to confirm the fix and a re-test every couple of years, since a tripped fan or new crack can let levels rise again.
If your Ault home tested above 4 pCi/L, a properly designed mitigation system is a permanent, documented fix worth far more than the gas it removes. To connect with a vetted local mitigator, get in touch through our contact page.
Test your home for radon
Radon is invisible and odorless, so a test is the only way to know your level. A short-term kit gives a first reading in days; a digital monitor tracks it over time.
| Product | Why | Buy |
|---|---|---|
 AirChek Charcoal Radon Test Kit | Lab fee usually included; EPA short-term protocol. | Amazon — $21.95 |
 First Alert RD1 Radon Test Kit | Widely stocked; 48-hour charcoal test. | Amazon — $16.98 |
 Airthings Corentium Home | Digital monitor with a long-term average. | Amazon — $142.99 |