Radon Mitigation Pros in Portland, OR

Finding a qualified radon mitigation contractor in Portland sounds simple until you’re three quotes in and realize two of the guys don’t hold an NRPP or NRSB credential and the third won’t show you their pre/post test results. Portland’s housing stock — dense with mid-century basements, craftsman crawlspaces, and new construction in the West Hills — creates a patchwork of radon risk that generic national advice misses entirely. This directory exists so you can skip the guesswork and go straight to vetted contractors who know Multnomah County’s geology.

How to Choose a Radon Mitigation Contractor in Portland

• Verify the credential before the quote. Ask for their NRPP or NRSB certification number and look it up at aarst-nrpp.com. In Oregon, there’s no state licensing requirement for radon contractors — certification is the only accountability mechanism that exists.
• Separate the tester from the mitigator. An ethical contractor won’t sell you a mitigation system based on their own test alone. If someone quotes you a full install on the first call without an independent baseline measurement, walk away.
• Ask about post-mitigation testing. The job isn’t done when the fan is running. A post-mitigation test 24–48 hours after install (ideally with a certified measurement professional’s short-term test kit) is the only way to confirm your levels dropped below 4 pCi/L.
• Get the warranty in writing. Standard ASD (active soil depressurization) systems come with a 1–5 year warranty on labor and a manufacturer warranty on the fan. If a contractor won’t commit that in a contract, that’s your answer.
• Check for crawlspace experience. Portland has a lot of older homes with vented crawlspaces rather than basements. ASD installation in a crawlspace requires a sealed vapor barrier and different pipe routing — not every mitigation contractor has done it cleanly. Ask specifically.

Pro Tip: Oregon Health Authority maintains a list of certified radon professionals. Cross-reference any contractor you find here against that list — it takes two minutes and eliminates anyone operating outside best practices.

What to Expect

A standalone radon test runs $150–$400 depending on whether you’re using a certified professional’s short-term charcoal canister or a continuous electronic monitor (the latter is more useful for real estate transactions with tight timelines). If mitigation is warranted, a typical ASD system installation in Portland runs $800–$1,500 for a standard single-point basement or crawlspace job, with more complex multi-point systems or finished basement installs trending toward the top of that range. Most installs are completed in a single day.

Reality Check: The cheapest quote is almost never the right one here. Underpowered fans, improperly sealed penetrations, and missing post-test verification are the three ways a cheap install fails — and you won’t know it until your next test comes back at 6 pCi/L. The difference between a $900 job and a $1,300 job is usually a better fan spec, a cleaner seal, and a contractor who actually shows up for the post-mitigation reading.

Local Market Overview

Portland sits in EPA Radon Zone 2, meaning elevated indoor radon is a genuine but often overlooked risk — particularly in neighborhoods built on the volcanic soil deposits of the West Hills and in older Eastside homes with unsealed basements and minimal sub-slab ventilation. Oregon doesn’t mandate radon disclosure in real estate transactions the way some states do, which means mitigation issues frequently surface after closing rather than before, putting homeowners in a reactive position rather than a proactive one.