Questions to Ask Duct Cleaning Pros.

Ensuring your air duct cleaning delivers real value and improved indoor-air quality starts with asking the right questions before hiring a contractor. A thorough vetting process helps distinguish professional, reputable services from those that offer superficial or incomplete work. By focusing on credentials, methods, pricing transparency, and safety practices, you’ll gain confidence in the company you choose and clarity on what to expect. Below are the essential questions to guide your selection process.

Credentials and Experience

Begin by confirming the contractor’s qualifications and track record.

Are you NADCA-certified or do you follow NADCA’s ACR standards?
Certification by the National Air Duct Cleaners Association (NADCA) indicates adherence to rigorous source-removal cleaning protocols and ongoing training.
How many years have you been in business, and how many duct-cleaning jobs have you completed?
Experience with a variety of HVAC configurations—from single-zone homes to complex commercial systems—demonstrates expertise.
Can you provide references from recent customers?
Speaking directly with past clients offers insights into reliability, quality of work, and customer satisfaction.
Do you carry any industry-specific memberships or additional certifications?
Affiliations with the Environmental Protection Agency guidelines, local HVAC associations, or mold remediation organizations further validate professionalism.

Equipment and Cleaning Methods

Next, understand the tools and techniques they will employ to ensure thorough cleaning.

What type of vacuum system and filtration do you use?
Professional negative-pressure HEPA vacuums prevent dislodged debris from escaping into living spaces, unlike standard shop vacs.
Which mechanical agitation tools do you utilize?
Rotary brushes, compressed-air whips, and pneumatic devices sized to each duct diameter ensure deep source removal from trunks and branches.
Do you perform pre- and post-cleaning inspections with cameras?
Visual documentation confirms areas of concern and verifies that cleaning was effective.
How do you contain dust and debris to protect my home during service?
Proper containment—plastic sheeting, sealing registers, and negative-pressure barriers—minimizes cross-contamination.

Pricing, Scope, and Guarantees

Transparent pricing and clearly defined scope of work prevent surprise charges and ensure you get what you pay for.

Can you provide a detailed, itemized written estimate?
The estimate should break out base fees, per-register or per-return charges, and add-ons such as coil cleaning or mold treatment.
What services are included in your standard package, and what counts as an extra?
Clarify whether cleaning coils, blower compartments, UV-C lamp installation, or dryer-vent service incurs additional costs.
Do you offer any satisfaction guarantees or warranties on your work?
A written guarantee that the job meets NADCA or EPA standards—and a defined remediation plan if it doesn’t—signals confidence in service quality.
How do you handle unforeseen issues discovered during cleaning?
Require written change orders and approval before any additional work or charges take place, avoiding verbal-only agreements.
Are there any coupons, seasonal promotions, or maintenance plans that could reduce my costs?
Inquire about package deals—bundling HVAC tune-ups or filter upgrades—to maximize value without sacrificing quality.

Insurance, Safety, and Compliance

Finally, verify that the contractor safeguards your property, health, and legal responsibilities.

Do you carry general liability, pollution liability, and workers’ compensation insurance?
Proof of coverage protects you from financial responsibility for accidents, property damage, or health claims resulting from service.
What safety protocols do you follow to protect technicians and occupants?
Proper use of PPE (respirators, gloves, goggles), chemical handling procedures, and containment measures ensure minimal exposure to dust, mold, and cleaning agents.
How do you comply with EPA guidelines on chemical use and mold remediation?
Contractors should reference EPA mold guidance and only apply biocides when necessary, after mechanical removal, under controlled conditions.
Can you demonstrate your certifications, licenses, and professional affiliations?
Always inspect physical or digital copies of ASCS/ASCDP credentials, business licenses, and NADCA membership to confirm legitimacy.
What post-service reporting do you provide?
Expect comprehensive before-and-after documentation, a summary of work performed, and recommendations for ongoing maintenance to prevent future issues.

Conclusion

Asking these targeted questions to ask duct cleaning pros empowers you to select a contractor who delivers thorough, safe, and reliable service. By verifying credentials and experience, understanding equipment and methods, demanding pricing transparency, and ensuring proper insurance and compliance, you set clear expectations and minimize risk. For a broader vetting framework, revisit how to choose an air duct cleaning contractor and delve deeper into professional standards with NADCA certification explained. When evaluating contractor integrity and warning signs, consult red flags in duct cleaning services to avoid subpar providers.