If your Arvada, CO basement tested above the EPA's radon action level of 4 pCi/L, the next question is almost always the same: what actually gets installed, and how is a basement system different from the crawl space or slab setups described elsewhere on this site? Here's what a basement-specific system looks like in practice.
What Is a Basement Radon Mitigation System?
A basement radon mitigation system is a network of sealed piping, one or more suction points beneath or beside the foundation, and an in-line fan that pulls radon-laden soil gas from under the slab and vents it above the roofline before it can enter the living space. The most common version installed in Jefferson County basements is an active sub-slab depressurization (ASD) system, detailed in how active sub-slab depressurization systems work.
How Does a Basement Radon Mitigation System Work in an Arvada, CO Home?
The licensed operators in our network typically drill one 2-inch suction point through the basement slab, insert a PVC pipe sealed with polyurethane caulk, and route it through a wall or closet to a roof-mounted or exterior fan that discharges above the roofline, at least 10 feet from any window or door per the ANSI/AARST SGM-SF-2020 mitigation standard. More on the underlying method is covered in active soil depressurization basics for Arvada homes.
Many Arvada basements already have a sump pit, and where that pit penetrates the slab and drains to gravel below, sealing its lid and running the suction pipe directly from the sump often works better than drilling a second hole — it uses an existing opening into the sub-slab aggregate rather than creating a new one.
How Is a Basement System Different From a Crawl Space or Slab-Only System?
A basement system pulls air from beneath a poured concrete slab, while a crawl space system typically depressurizes beneath a heavy plastic vapor barrier (sub-membrane depressurization) laid over exposed soil, since there's no slab to seal against. Homes with a finished basement plus an attached crawl space or garage slab often need both approaches combined into one manifolded system.
This matters in Arvada and greater Jefferson County because many split-level and multi-level homes built from the 1960s through the 1980s have exactly this mixed foundation layout — basement plus crawl space under an addition — which is why a single suction point rarely covers the whole house.
Who Is Allowed to Install a Radon Mitigation System in Colorado?
Colorado does not require a general state contractor license specifically for radon work, but the Colorado Department of Public Health & Environment (CDPHE) directs homeowners toward professionals certified through the National Radon Proficiency Program (NRPP) or the National Radon Safety Board (NRSB) before any mitigation contract is signed.
Ask any installer for their current NRPP or NRSB mitigation certification number, and confirm it's active — it's the credential CDPHE points to when Colorado homeowners ask how to vet a mitigation professional.
How Do I Know the System Is Actually Lowering Radon Levels?
The only reliable way to confirm a system works is a post-mitigation radon test, run for a minimum of 48 hours with the system operating continuously, placed in the lowest livable level of the home under closed-house conditions consistent with EPA testing protocol. A properly functioning system should bring results below 4 pCi/L. If you haven't tested yet, see the average radon levels guide for Arvada and Boulder to understand what your number means before deciding whether mitigation is needed.
Most installers also mount a U-tube manometer or digital gauge on the vent pipe so the fan's suction can be checked visually at any time — if the gauge reading changes or the fan goes silent, that's the first sign the system needs service.
What Does a Basement Radon Mitigation System Cost in Arvada, CO?
Pricing depends on the number of suction points needed, whether an existing sump pit can serve as the primary entry point, fan placement, and any drywall or trim repair required after piping runs through finished space — all factors that vary house to house. For a detailed breakdown of what Arvada homeowners typically pay, see Radon Mitigation Cost in Colorado: What Arvada Homeowners Pay.
This article is for general informational purposes and does not replace an in-home radon test, a professional inspection, or guidance from CDPHE. Radon levels and mitigation needs vary by property; always test before and after any mitigation work.