About Drennen Custom Contracting
Drennen Custom Contracting is a local, family-run Northern Colorado company serving the community since 1973. Today, roofing and radon are Drennen's two defining specialties. Each has its own trained team, regulated or technical scope, written documentation, and long-term service support.
Two Specialties. One Building-Wide Perspective.
Roofing
Complete roof systems, repairs, Class 4 and SBS materials, inspections, certifications, ventilation, flashing, warranties, and detailed project scopes.
Radon
Colorado-licensed measurement and mitigation oversight, existing-home systems, crawl spaces, passive activation, repairs, real estate work, new construction, and large-building testing.
Drennen's radon professionals maintain credentials through the National Radon Proficiency Program and the American Association of Radon Scientists and Technologists.
Why the Combination Matters
A roof is not an isolated surface. It interacts with roof decking, attic ventilation, penetrations, siding, drainage, and the rest of the building envelope. Understanding those connections allows Drennen's roofing team to identify problems that a surface-only inspection would miss and to write scopes that account for the full system.
A radon system is similarly embedded in the building. It interacts with slabs, crawl spaces, framing, electrical work, siding, attic conditions, roof penetrations, and trade sequencing. Proper design and installation require understanding how the building is constructed, not just where the pipe exits.
Roofing and radon remain distinct specialties with separate teams, separate licensing, and separate documentation. What they share is a single company that understands the whole structure — which matters when a project involves both systems or when a problem in one area has a root cause in another.
How Drennen Works
- Detailed scopes that identify what is included
- Current licenses, insurance, warranties, and credentials available for verification
- Real Drennen project photography and anonymized project examples
- Post-work documentation and testing where applicable
- A local office and long-term service presence
- Clear communication with homeowners, Realtors, builders, and property managers
Meet the Team
Arnie
Founder
Arnie founded Drennen Custom Contracting in 1973, building the company one project—and one relationship—at a time. His commitment to quality craftsmanship, honest service, and treating customers like neighbors established the values that still guide DCC more than 50 years later. Although the company has grown and evolved, Arnie's influence remains at the heart of everything we do. Around here, he is not just the founder—he is where the Drennen story began.
Scott
Director of Roofing
For Scott, roofing is part profession and part family legacy. He grew up around the Drennen office and began working alongside his father, DCC founder Arnie Drennen, as a teenager. Those early years gave him a hands-on education in craftsmanship, problem-solving, and treating customers fairly. Today, Scott's passion and dedication drive DCC's roofing department. He is committed to giving Northern Colorado homeowners the best-quality roof possible at the lowest responsible cost—because a great roof should protect both your home and your budget.
Rafe
Operations Director
Rafe is the mastermind behind the moving parts of Drennen Custom Contracting. A sharp thinker and true jack-of-all-trades, he oversees every department while keeping the company focused on its larger mission. Whether he is solving an operational puzzle, improving a process, or helping a department rise to a new challenge, Rafe is constantly pushing DCC forward. His high standard of excellence shapes everything we do and ensures that, even as the company grows, quality, integrity, and service remain at the center of the operation.
Poppy
Office Manager
Poppy works primarily behind the scenes, making sure the people—and the systems supporting them—have what they need to succeed. She cares for the DCC team through human resources, analyzes company data, and serves as the Directors' primary support as they lead their departments. As Rafe's right hand, Poppy helps turn DCC's high standards into consistent everyday practices. Her work keeps the company organized, the team supported, and every department focused on what matters most: keeping our community happy, protected, and safe.
Seth
Director of Radon Mitigation
Seth has the kind of engineer's brain that genuinely enjoys a difficult problem. Complex foundations, unusual crawlspaces, and challenging system designs are where his creativity and technical thinking shine. As Director of Radon Mitigation, Seth leads his team with a clear goal: install the most effective, thoughtfully designed, and aesthetically pleasing radon systems possible. He stays current with evolving technology, research, and industry practices so every system reflects the best knowledge available—not simply the way things have always been done.
Dan
Director of Radon Measurement
Dan brings decades of radon experience—and an impressive supply of curiosity—to every home, estimate, and conversation. His commitment to continuing education keeps Drennen at the forefront of radon measurement and mitigation practices, while his passion for community outreach regularly takes him beyond the office. Whether he is evaluating a property, helping design the right solution, or providing a free educational lecture, Dan has a gift for making complex radon science practical and understandable. For him, knowledge is most valuable when it helps keep our Northern Colorado community safe.
Sierra
Administrative Assistant
Sierra is one of the friendly voices helping customers find their way through Drennen Custom Contracting. As an Administrative Assistant, she enjoys connecting with people by phone and email, answering questions, coordinating details, and making sure no one is left wondering what comes next. She might not have all the answers—but she will get you to someone who does. With her helpful nature and welcoming approach, Sierra makes it easier for customers to reach the right person, find the information they need, and feel cared for along the way.
Bo
Administrative Assistant
Known around the office as "Captain Sunshine," Bo brings warmth, positivity, and a reliably cheerful presence to Drennen Custom Contracting. As an Administrative Assistant, Bo helps customers and coworkers by answering questions, coordinating information, and making sure important details reach the right person. Whether the office is running smoothly or the day has taken an unexpected turn, Bo is always ready to lend a hand—and usually brighten the room in the process. That combination of helpfulness and good humor makes Bo an important part of keeping DCC welcoming, organized, and moving forward.
Serving Northern Colorado
Drennen serves Fort Collins, Loveland, Windsor, Wellington, Timnath, and surrounding Northern Colorado communities. Service availability, travel, local permitting, and project type are confirmed for each address.
Start With the Problem You Need to Solve
Tell us whether the concern is roofing, radon, a real estate deadline, new construction, or a project involving both building systems.