Arizona Preliminary Twenty-Day Notice for HVAC Contractors
In the bustling Phoenix metro area, the rapid pace of commercial development creates unique challenges for HVAC subcontractors. Large rooftop RTU arrays are a common sight on big-box retail and strip-mall rooftops, with the initial roof curb setting happening early in the construction process. This creates a gap between early work like roof curb installation and later tasks such as refrigerant charging and T&B at project completion. The intense Arizona summer heat and unpredictable monsoon season further complicate scheduling, making it crucial to understand the timing of notice requirements to protect payment rights.
Arizona has one of the broadest preliminary notice requirements in the country. Missing the deadline eliminates lien and payment bond rights — and unlike most states, even general contractors must file.
The Deadline
| Notice type | Preliminary Twenty-Day Notice |
| Governing statute | A.R.S. § 33-992.01 |
| Deadline | 20 days from first furnishing of labor, services, or materials |
The deadline is strictly enforced.
When Does the Clock Start for HVAC Contractors?
In the Phoenix metro area, HVAC subs often set roof curbs during the dry-in phase of commercial builds, well before RTU units are craned into place. This early structural work is considered first furnishing, even if it feels preliminary. Additionally, in Arizona's scorching summer heat, equipment might be staged in a covered exterior mechanical yard before installation, adding another layer of complexity to determining the start of the notice period.
The exact legal definition of "first furnishing" is set by A.R.S. § 33-992.01. This operational description does not substitute for the statutory definition.
Worked Example: Chandler — rooftop RTU array installation on a new-construction 18,000 sq ft multi-tenant retail strip
An HVAC subcontractor was contracted by the GC for a Chandler strip-mall build. On day one, the crew mobilized to set roof curbs and install the duct-drop framing through the roof deck before the RTUs were scheduled for delivery — a standard sequencing on Arizona shell-and-core retail projects. The sub's PM logged the mobilization internally but assumed the notice clock started when the rooftop package units were craned into position the following month. The RTUs arrived, were set, and refrigerant line sets were begun before anyone reviewed the original mobilization date.
| Event | Date |
|---|---|
| First furnishing | February 10, 2025 |
| Notice must be served by | March 2, 2025 |
| Deadline | 20 calendar days (A.R.S. § 33-992.01) |
If the notice is not served by March 2, 2025, lien rights are at risk regardless of work completed or amounts unpaid.
Three Ways Arizona HVAC Contractors Lose Their Lien Rights
N. Early Mobilization as First Furnishing
In the Phoenix metro area, setting roof curbs and duct framing on shell-and-core builds is often the first mobilization. This work is considered furnishing, even if it feels like preparatory work.
N. Monsoon Season Delays
Monsoon season can interrupt Arizona commercial HVAC commissioning schedules, pushing T&B months after duct rough-in. This delay can affect the perception of when work is completed.
N. Rapid Project Pace and Documentation
The fast pace of Phoenix metro projects means a sub's crew may mobilize, demobilize, and return multiple times before startup. The first mobilization date is frequently undocumented, risking payment rights.
Who Must File?
Virtually all claimants, including subcontractors, material suppliers, equipment lessors, and specialty contractors. Arizona has one of the broadest filing requirements in the country.
Who Is Exempt?
Laborers who are employees of the direct contractor or a subcontractor (wage earners).
How to Serve the Notice
The notice must be served by certified mail, registered mail, or personal delivery to the owner, the direct contractor (general contractor), and the construction lender (if applicable).
Statutory Notice Text
The following text must appear on the notice verbatim. Arizona statute requires this notice text to be rendered in BOLD face type.
NOTICE: THIS IS NOT A LIEN. This is a notice required by Arizona law to be given within twenty days of first supplying labor, professional services, materials, machinery, fixtures or tools to a construction project. It does not mean there is a problem with payment. This notice protects the right to file a lien or assert a claim against a payment bond if payment is not received.
What Happens When a Arizona HVAC Sub Doesn't File
In the city of Gilbert, an HVAC subcontractor was engaged to install a rooftop package unit array on a new multi-tenant strip mall. During the early construction phase, the crew set the roof curbs and framed duct supports, thinking the clock started ticking only after the RTUs were delivered and installed weeks later. However, the relentless Arizona sun and the looming monsoon season meant that the refrigerant charge and T&B were delayed, causing confusion about when the notice period actually began. This oversight led to a potential risk of losing payment rights, highlighting the importance of tracking all phases of work accurately.
HVAC-Specific Questions
On an Arizona commercial job, we set roof curbs and duct framing during dry-in, then came back six weeks later when the RTUs were delivered. Did our notice clock start at the roof-curb work or at RTU delivery?
In Arizona, the notice clock starts with the first furnishing, which includes setting roof curbs and duct framing during dry-in. This early work counts as the start of your contractual obligations, not the later RTU delivery.
Monsoon season pushed our Arizona commissioning schedule back by eight weeks. Does the startup and T&B date affect when our notice clock started?
The notice clock in Arizona starts with the first furnishing, not the startup or T&B date. Delays due to monsoon season do not alter the initial start date of your notice period.
We staged our RTUs in the mechanical yard of an Arizona job site for two weeks while the roof was being finished. Did that delivery to the yard start our notice clock before we ever touched the roof?
In Arizona, staging equipment in a mechanical yard does not start the notice clock. The clock begins with the first actual furnishing of labor or materials on the project site, such as setting roof curbs or duct framing.
Arizona Preliminary Twenty-Day Notice: Standard FAQs
As an Arizona HVAC contractor, understanding the nuances of our unique climate and construction pace is crucial.
What is the "30% Rule" for Arizona Preliminary Notices?
Under Arizona law, if the actual total price of your work exceeds the estimated amount on your original notice by more than 30%, you must serve an amended notice to protect the additional amount.
This is general information based on Arizona statutes, not legal advice.
Are General Contractors exempt from filing in Arizona?
No. Arizona is unique because virtually all claimants, including direct contractors (general contractors), must serve a Preliminary 20-Day Notice to secure their lien rights.
This is general information based on Arizona statutes, not legal advice.
See the Full State Deadline Guide
For a complete breakdown of all filing requirements, project-type rules, and deadlines, see the Arizona Preliminary Notice guide.
File the Moment You Mobilize
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This page provides general information about Arizona's construction lien law and is not legal advice. Consult a licensed Arizona construction attorney for guidance on your specific situation.