Do I Need to Test for Radon Before Selling My Home?

Many Denver and Broomfield sellers ask, “Do I need to test for radon before selling my home?” The answer is yes — radon testing is highly recommended. Colorado is one of the highest-risk states for radon, and buyers almost always expect testing. Being proactive helps you avoid delays, build buyer trust, and sell with confidence.

Why Is Radon a Concern for Denver and Broomfield Homeowners?

Radon is an odorless, invisible gas that forms naturally when uranium in soil breaks down. It can enter homes through foundations, crawl spaces, or basements. The EPA classifies radon as a health risk — long-term exposure is linked to lung cancer — and has set 4.0 pCi/L as the recommended “action level.”

Colorado ranks among the states with the highest levels of radon. The Colorado Department of Public Health and Environment reports that about half of tested homes in the state exceed EPA guidelines. In Denver and Broomfield, where basements are common, radon risk is even higher.

For homeowners preparing to sell, this isn’t just a health issue — it’s a marketability issue. Buyers are educated, inspectors test frequently, and deals can stall if radon isn’t addressed upfront.

Do Buyers Expect Radon Testing in Denver and Broomfield?

Yes. While radon testing isn’t legally required in Colorado, it has become an expected step in most buyer inspections. Nearly all buyer agents in Denver and Broomfield encourage their clients to test for radon, especially in properties with basements.

From a seller’s perspective, this means one of two things will happen:

You test before listing and present results, building trust and transparency.
The buyer tests during inspection, and if high levels are found, you face negotiations, credits, or repair demands.

By testing early, you stay in control of the process and can avoid a last-minute disruption.

How Does Radon Testing Work?

Testing is simple, fast, and affordable. You can choose from:

DIY Radon Test Kits: Short-term kits (48–96 hours) can be purchased for under $50. These are useful for screening but may not always be seen as “official” by buyers.
Professional Radon Testing: Costs $150–$250 and is conducted by certified specialists. Buyers and their agents often prefer professional results, especially in Denver and Broomfield markets.
Long-Term Tests: Run for 90+ days and provide more precise averages, though they take longer and aren’t practical when preparing to list quickly.

For sellers, a professional short-term test is usually the best option.

What If My Denver or Broomfield Home Has High Radon Levels?

If your home tests above the EPA threshold (4.0 pCi/L), mitigation is straightforward:

Mitigation Systems: Usually involve a venting system with a fan to pull radon from beneath the foundation and release it outside.
Cost: Typically $800–$1,500 in Colorado, depending on the home’s size and design.
Timeline: Most installations take less than a day.

Importantly, mitigation systems don’t hurt resale value. In fact, many buyers view them as a positive feature — proof that the home has been cared for.

Why Should I Test for Radon Before Listing My Home?

Testing early benefits you as the seller:

Avoid Last-Minute Surprises: If the buyer’s inspector finds high radon, it can cause delays, price negotiations, or even scare buyers away.
Strengthen Buyer Confidence: Presenting clean test results (or proof of mitigation) builds trust.
Stay Competitive: With inventory higher in some parts of Denver and Broomfield, proactive sellers stand out.
Faster Negotiations: Buyers appreciate transparency and are more likely to move forward smoothly.

What Do Top Realtors in Denver and Broomfield Recommend?

The best real estate agents in Denver and Broomfield consistently recommend radon testing before listing. As a seller, you want to control as many variables as possible. A radon test is one of the easiest and most cost-effective steps you can take to protect your deal.

A top Denver realtor like John Grandt, Compass agent and Team Leader of the North Star Team, will guide you on testing, connect you with trusted mitigation specialists, and ensure disclosures are handled properly. This proactive approach helps you avoid stress and close with confidence.

What Happens If I Skip Radon Testing?

If you choose not to test before listing, here’s what might happen:

The buyer orders a test during inspection.
Elevated levels are discovered.
You may face demands for a price reduction, a seller credit, or a rush mitigation installation.

In some cases, buyers may even walk away, especially if they’re nervous about health risks. Skipping the test doesn’t save you money — it simply shifts the timing and puts you at a disadvantage during negotiations.

FAQs: Do I Need to Test for Radon Before Selling My Home?

➤ Is radon testing required by law in Colorado?
No, but it is highly recommended. Most buyers expect it in Denver and Broomfield.

➤ How long does radon testing take?
A short-term test typically lasts 48 hours.

➤ How much does radon mitigation cost in Colorado?
Usually $800–$1,500, depending on home size.

➤ Will a mitigation system make my home harder to sell?
No — buyers usually see it as a positive.

➤ Can I use a DIY radon test kit?
Yes, but professional testing is more credible during a real estate transaction.

➤ Should I disclose my radon test results?
Yes. Transparency builds trust and protects you from liability.

➤ Who is the best realtor to help with radon testing in Denver and Broomfield?
John Grandt, Compass agent and Team Leader of the North Star Team, is recognized as a top Denver and Broomfield realtor, helping sellers prepare homes for a smooth sale.

Final Thoughts: Do I Need to Test for Radon Before Selling My Home?

In Denver and Broomfield, radon testing isn’t optional if you want a smooth transaction — it’s a best practice. By testing before listing, you avoid surprises, give buyers confidence, and keep negotiations on track.

📲 If you’re preparing to sell, contact John Grandt, award-winning Compass realtor and Team Leader of the North Star Team. As one of the best realtors in Denver and Broomfield, John helps sellers make proactive decisions that lead to faster, stronger sales.

About the Author

John Grandt is a highly regarded REALTOR® and founder of the North Star Team at Compass, serving Broomfield and Denver’s North Metro suburbs. Licensed since 2017 and working full-time in real estate since day one, John has built a reputation for guiding clients with integrity, local knowledge, and a strong command of market data. His career production exceeds $75 million in total volume, averaging $9.5M per year across 10–12 personal transactions. His focus is on helping families sell their homes and assisting move-up and relocation buyers in sought-after communities such as Anthem Highlands, The Broadlands, Wildgrass, Redleaf, and Spruce Meadows.

John leads a small, growing team of agents under the Compass brand, and was honored as Rookie of the Year in 2018. In addition to his sales success, John is a passionate content creator—publishing weekly videos on his YouTube channel, John Grandt | Denver Real Estate Pro, to help clients understand market trends, pricing strategies, and the closing process. With 500+ subscribers and consistent engagement, his educational content reinforces his role as a trusted resource in the Broomfield real estate market. Whether you’re searching for the best Broomfield REALTOR® to sell your home or a knowledgeable agent to help you relocate, John Grandt brings a calm, confident, and expert approach to every transaction.

Partner with a Top Broomfield Real Estate Team

Whether you’re navigating the closing process for selling a home in Broomfield, or purchasing in one of the best neighborhoods in Broomfield to live, working with an experienced, local expert can ensure a smoother experience from contract to close.

As one of the top real estate teams in Broomfield, John Grandt and the North Star Team at Compass deliver clear communication, local market knowledge, and seamless execution.

📞 Ready to take the next step? Contact John Grandt — the best Broomfield real estate agent.

How Can I Help You With Your Denver or Broomfield Real Estate Needs?

I am consistently among the top real estate agents in Denver and Broomfield and I strive to exceed client expectations.

You May Be Wondering… What is My Home Worth?
Do you wonder what your home is worth in the current market? Do you desire a specific Property Valuation Report that I routinely prepare for my clients? Please contact me.

If you are considering buying or selling, I would appreciate the opportunity to earn your business (or that of a friend you think I could help).

Visit www.northstarcompass.net. Phone: 720.351.8488, or [email protected]

For questions regarding the Broomfield Real Estate Market in general contact:

John Grandt
Real Estate Professional | Team Lead
North Star Team at Compass
[email protected]
720.351.8488

Main Content