Security of Payment for HVAC & Mechanical Contractors | PayClaim

HVAC & Mechanical Contractors: Complex Work, Complex Payment Disputes

HVAC and mechanical contractors deliver some of the most technically complex and high-value work on construction projects. Air conditioning systems, mechanical ventilation, chiller plants, BMS integration — this is specialist, high-cost work. And because of that high value, head contractors frequently dispute, delay, or partially pay HVAC and mechanical invoices, knowing that the amounts involved give them significant leverage.

Australia’s Security of Payment laws give HVAC and mechanical subcontractors a legally enforceable right to recover unpaid invoices — fast and without lawyers.

Why HVAC and Mechanical Contractors Face Payment Disputes

  • High-value progress claims: Large invoice amounts make head contractors reluctant to pay without looking for grounds to dispute
  • Commissioning disputes: Claims that systems aren’t commissioned to spec — even with sign-off from engineers and building managers
  • Variation disputes: Design changes, additional zones, upgraded equipment, or extra cabling ordered during the project then disputed at invoice
  • BMS integration disputes: Arguments about whether BMS integration is complete, who is responsible for which elements
  • Extended retention: Significant retention amounts held for extended periods beyond the defects liability period
  • Sub-subcontract exposure: Mechanical subs working under an M&E contractor who hasn’t been paid by the head contractor

Your Security of Payment Rights

HVAC and mechanical work is explicitly construction work under Security of Payment legislation in every Australian state and territory. Your rights include:

  • Serving a formal payment claim — the head contractor must respond within 10–15 business days
  • Applying for adjudication — an independent, binding determination in 10 business days
  • Enforcing the determination as a court judgment

There is no dollar limit. HVAC contractors with high-value mechanical contracts can claim any amount through the SOP process.

How PayClaim Works for HVAC and Mechanical Contractors

  1. Start online: Provide details of the mechanical contract, the unpaid invoice, and the head contractor or principal. Quick assessment.
  2. We confirm your entitlement: Our team reviews your contract position and advises on your Security of Payment rights.
  3. Payment claim prepared and served: A fully compliant payment claim is drafted and served on the correct party on time.
  4. Adjudication managed: If the claim is disputed or ignored, we handle the full adjudication process including technical document preparation.

Flat fee. No lawyers. Most HVAC claims are resolved within 10–20 business days.

Your Systems Are Running — Now Get Your Payment Moving

You delivered a fully functional mechanical system. Don’t let the head contractor use technical complexity as a shield against paying you. Start your free claim with PayClaim today.

Start Your Free Claim →