1st DeFense Radon Testing and Mitigation, LLC

HomeAdvisor screened and approved seal

HomeAdvisor Screened & Approved

This service professional has passed the HomeAdvisor screening process.

Learn about our screening process
Learn about our screening process

99% Recommended

5 Years In Business

Company Details


9120 Hillside Trail South
Cottage Grove, MN 55016


  • Mon: 7:00 AM - 8:00 PM
  • Tue: 7:00 AM - 8:00 PM
  • Wed: 7:00 AM - 8:00 PM
  • Thu: 7:00 AM - 8:00 PM
  • Fri: 7:00 AM - 8:00 PM
  • Sat: 7:00 AM - 8:00 PM
  • Sun: NaN:NaN AM - NaN:NaN AM
View All Details & Credentials


Service Details

    Areas of Expertise

    • Radon Gas - Testing
    • Radon Gas - Abatement
    View All Offerings and Cities Served

    Cost Information

    • Free Estimates


    122 Verified Reviews
    • 5
    • 4
    • 3
    • 2
    • 1

    Highly rated for

    • Quality
    • Value
    • Customer Service
    Showing 1-10 of 122 reviews Showing 0 reviews
    5.0 Donovan F. Mahtomedi, MN

    Very timely and responsive . Explained everything very well.

    5.0 Eugene H. Farmington, MN

    Responded promptly to my request. Evaluated job before giving me the bid and was very fair in the cost. Steve explained all he was going to do. Very responsive to all our questions. Did a very neat job and the clean-up was great. Very professional.


    Very nice and ensured safety with masks and cleaned up beyond what I expected. Responded promptly to our request and communicated clearly on expected arrival.

    3.5 Carin B. Saint Paul, MN

    Originally contacted for a job in St. Paul and then reached out when we put in an offer farther north. I think the tech over extended himself and has issues with the timeline. Very nice, but maybe should have realized the commute would cause issues.

    5.0 Melissa P. Saint Paul, MN

    Steve was excellent. He was very informative, responsive and transparent. I was impressed with his quick response to our initial call.

    5.0 Mark R. Saint Paul, MN

    Professional and communicative. Excellent install.

    5.0 Spencer M. Saint Paul, MN

    Great customer service. Was one small issue that they quickly followed up on and resolved the next morning.

    5.0 Conner K. St. Anthony, MN

    Steve is super communicative, easy to follow the work to be done (talks to you like a human, not radon expert) and is awesome! :)

    5.0 Cliff L. Hastings, MN

    On time,clean up behind and during install. Quick,waste no time.


    Professional and very thorough

    Showing 1-10 of 122 results Showing 0 of 0 results

    HomeAdvisor allows Service Professionals to post information about themselves and their business on their profile. HomeAdvisor does not review or verify the information representations set forth in those profiles as they are self-reported by the Service Professional.

    HomeAdvisor verifies state-level licensing where applicable - note: some states require local or county level licensing and you should verify whether or not your pro is properly licensed.
    To find more licensing information for your state, visit our Licensing Requirements page.

    Seal of Approval

    What is the screening process that Service Professionals go through in order to become members of the HomeAdvisor network?

    1. Verify Trade License
      HomeAdvisor checks to see if the business carries the appropriate state-level license.
    2. Verify Insurance
      As a part of our screening process, we encourage professionals to carry general liability insurance. We require coverage for hundreds of services.
    3. Verification of State Business Filings
      For business types that require a Secretary of State filing, we confirm that the business is in good standing in the state in which it is located.
    4. Criminal Records Search
      HomeAdvisor uses 3rd party data sources to conduct a criminal search for any relevant criminal activity associated with the owner/principal of the business.
    5. Sex Offender Search
      We confirm that the owner/principal is not listed on the official state Sex Offender web site in the state in which the owner/principal of the company is located.
    6. Bankruptcy Search
      We use 3rd party data sources to check the history of the principal/owner of the business for bankruptcy filings by or against them.
    7. Legal Search for Civil Judgments
      We use 3rd party data sources to check the principal/owner of the business for state level civil legal judgments entered against them.
    8. Liens Search
      We use 3rd party data sources to check the principal/owner of the business for liens placed against them.
    9. Identity Verification (SSN)
      HomeAdvisor verifies the social security number(s) of the owner/principal for identity check purposes. This check applies primarily to smaller business entities.
    10. Identity Verification (Reverse Phone Lookup)
      We conduct a reverse business phone lookup to identify records matching the phone number information provided by the business.

    NOTE: Member service professional information confirmed as described above may change or expire over time; while HomeAdvisor attempts to maintain accurate and up-to-date information, and confirms changes when notified, we cannot guarantee that profile and screening information is accurate. Therefore, we recommend that before working with a service professional you verify that information presented is still current and/or acceptable to you.
    Please see HomeAdvisor's Terms and Conditions for a full description of how we screen Service Professionals

    **Only for U.S. service professionals

    Final Step - Confirm Your Appointment:

    Confirm your appointment with on , - Change


    By clicking Confirm Appointment, you affirm you have read and agree to the HomeAdvisor Terms & Conditions, and you agree and authorize HomeAdvisor and its affiliates, and their networks of Service Professionals, to deliver marketing calls or texts using automated technology to the number you provided above regarding your project and other home services offers. Consent is not a condition of purchase.