Most dryer vent vendors were built for single-family homes and scaled up. A few were built for multifamily. The difference shows up in insurance, credentialing, documentation and resident handling — not in how well they clean a duct. Here is how to tell them apart before you sign.
The Scope Questions
Do you clean the full duct run? The only correct answer is from the dryer connection through to the exterior termination. Vendors who clean the accessible ends only are cleaning the two places lint is least likely to be a problem.
Do you verify airflow at every unit? Without it, nobody knows whether the work worked.
How do you handle rooftop terminations and vertical risers? If the answer is vague, they do not have the equipment. Ask what they carry.
The Documentation Questions
Do I receive before and after photos of every unit? Not a sample. Every unit. This is the compliance artifact — the reason the exercise has value beyond the vent itself.
Do you provide a deficiency report? Crushed ducts, disconnected runs, foil transitions in concealed spaces, failed backdraft dampers. A vendor who never finds deficiencies is not looking.
Do you issue a completion certificate referencing NFPA 211? This is what goes in your compliance file.
The Insurance and Credentialing Questions
What are your GL limits, and can you issue a COI with our exact additional insured wording? Ask for a sample certificate before you engage. Vendors who cannot produce one quickly will stall your compliance team for weeks.
Do you carry workers’ compensation in our state? Not a national policy that excludes your state. In your state.
Are you compliant in NetVendor / RealPage / VendorCafe? If your company runs vendor compliance through a platform, a vendor already verified in it can be property-assigned in days rather than weeks.
The Operational Questions
Are your technicians background-checked? They will be entering residents’ homes.
What is your process for units you cannot access? A documented re-attempt process, or do they simply bill you for units they never entered?
Who do I call during the project? A named contact, or a queue.
The Red Flags
- Lump-sum pricing with no reference to unit count or termination type
- No photo documentation, or “photos on request”
- Reluctance to name their insurance limits
- No workers’ compensation in your state
- A quote materially below the market band with no explanation of what is different
- Residential-first marketing and a commercial page bolted on
The Simple Test
Ask for a redacted sample photo report from a comparable property. A vendor who does this work properly will send one within the hour. A vendor who does not have one will explain why they cannot.
Request a quote and a sample report from Doctor Vent.