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Drennen Custom Contracting (Radon and Roofing)

Fort Collins Renovation Contractors
Ranked #1 in Fort Collins | Grade A+
5.00 (385 reviews)

Drennen Custom Contracting (Radon and Roofing)

Local contractor providing radon testing and mitigation along with roofing services. Office is located on E Trilby Rd in Fort Collins with weekday hours.

Why Homeowners Choose This Business

Homeowners frequently note clear communication, punctual crews, and tidy job sites. Projects are often completed in a single visit when feasible, with guidance on testing before and after mitigation. The team explains options and addresses questions without pressure.

Service Area

Fort Collins and surrounding Northern Colorado neighborhoods.


How This Business Compares

A quick local comparison based on ranking, review strength, and market visibility.
  • Ranks among the top local businesses in this market.
  • Performs at or above the local average for Google rating.
  • Has more Google review volume than many local competitors.
  • Shows strong customer satisfaction signals based on review quality and volume.

Services Covered

  Consultant
  Renovation Services
  Roofing Contractor
  Radon Mitigation
  Installations
  Radon Testing
  Passive to Active Radon Upgrade
  Repairs
  Roof Inspection
  Roof Repair
  Roof Replacement
  Vent Pipe Installation
  Attic Ventilation
  Leak Repair
  Shingle Roofing

Services include: radon testing, passive-to-active mitigation upgrades, full radon mitigation systems, post-install test support, and roofing inspections, repairs, and replacements.


Recent Reviews

5.00

(Based on 385 reviews)

Reviews consistently highlight courteous, on-time crews who explain the process and answer questions thoroughly. Many customers mention efficient installations—often completed in one day—and careful cleanup. Follow-up testing guidance and noticeable reductions in radon levels are recurring themes. Overall satisfaction reflects clear communication from estimate through completion.

Drennen Radon Mitigation team was very professional from the estimate to the challenges of installation. I highly recommend the service. Seth lead the team and made sure all of our concerns were handled to our liking. Ray and Garrett, took care of the electrical and concrete boring and did a fine job. We were very impressed with the whole process all finished in one day. Thank you Drennen!

I hired Drennen to update my passive radon mitigation to an active mitigation with a fan. Both the initial inspector and the technicians were incredibly patient with my questions and explained everything very well. The installation went very quickly and smoothly and the left we with a mitigation test to assess the efficacy of the new system. It was way easier than I expected, though definitely an investment.

Less than 24 hours after Drennen finished updating my radon system, and I couldn’t be happier. It was a true pleasure working with their team. They were on time, courteous, informative, and delivered high-quality work. Everything looks great and is working perfectly.

I feel confident that when we complete the post-installation test, we’ll see a noticeable improvement in radon levels, and I can move forward with real peace of mind. Highly recommend!

Drennen installed my radon mitigation system when we purchased our new construction home. I recently contacted them about checking our current level to make sure everything is working as it should. It was easy to get a convenient appointment time, the employees are all very friendly and helpful. I was given options for picking up a test kit or having one of their employees drop it off and set it up. It was great to learn that during radon awareness month they were offering a discount for both options. There were some changes with the appointment drop off/pick up time and Drennen did a great job of communicating throughout. Very pleased with their service.

Fantastic job of radon mitigation installation. The install crew was awesome, fast, and cleaned up afterwards. I couldn't imagine a better installation. After 24 hours my radon levels are below the guideline and I am very happy. Drennen made this whole process a breeze.

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Special Offers

Free Estimate

This business may offer free estimates for some services.


Frequently Asked Questions

They provide radon testing, installation of new mitigation systems, and upgrades from passive to active systems with a fan. Customers also receive guidance on post-install testing to verify results.

Many residential installations are completed in a day, depending on the layout and access. The team discusses the plan in advance and keeps homeowners updated during the visit.

Yes. Customers are commonly provided with instructions or a kit to confirm system performance after installation. The staff can explain how to place and read the test.

Roofing work generally includes inspections, repairs, and full replacements. They can assess issues such as leaks, damaged shingles, and age-related wear.

You can call the Fort Collins office during weekday business hours or use the website’s contact page to request a time. Appointments are typically set within standard working hours.
 Verified Listing

Opening Hours


  • Monday 8:30 AM – 4:30 PM
  • Tuesday 8:30 AM – 4:30 PM
  • Wednesday 8:30 AM – 4:30 PM
  • Thursday 8:30 AM – 4:30 PM
  • Friday 8:30 AM – 4:30 PM
  • Saturday Closed
  • Sunday Closed

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Business Details


Business Rating
5.00 (385 reviews) Pro Business
Address
608 E Trilby Rd, Fort Collins, CO 80525
Phone
Business Type
general_contractor

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