CRA GST/HST Duct Cleaning, Furnace Cleaning & Air Quality Service Audit — Montreal CPA Firm Near You: Defending Taxable Services, Equipment Costs, Subcontractors & ITCs

A CRA GST/HST Duct Cleaning & Air Quality Services Audit targets businesses providing:

• residential duct cleaning
• commercial HVAC duct cleaning
• furnace cleaning & tune-ups
• air-quality testing
• dryer duct cleaning (HVAC-related)
• sanitation & disinfectant fogging of HVAC systems
• negative-pressure duct extraction
• HEPA vacuum services
• coil cleaning & blower motor cleaning
• subcontracted duct-cleaning crews

CRA audits this sector heavily because duct cleaning involves 100% taxable services, high-value equipment, subcontractor helpers, strong seasonality, and inconsistent invoicing among small and medium HVAC-adjacent businesses.

Mackisen CPA Montreal specializes in defending duct-cleaning audits with complete job documentation, subcontractor validation, and ITC reconstruction.

Legal Foundation

Excise Tax Act

• s.165 — ALL duct cleaning, furnace cleaning, HVAC sanitation & air-quality services are fully taxable

• s.221 — GST/HST must be collected on every job

• s.169 — strict ITC documentation requirements

• s.141.01 — mixed-use asset allocation (truck, equipment, vacuums)

• Schedule IX — GST/HST rate based on location of HVAC system

• s.123(1) — defines “cleaning,” “maintenance,” “service,” “real property service”

Case Law

• CGI v. Canada — job location = GST/HST province

• Royal Bank v. Canada — incomplete invoices invalidate ITCs

• Northwest Company Inc. — supplier invoices must meet legal standards

• CRA rulings: duct cleaning, HVAC sanitation & furnace cleaning = 100% taxable, no exemptions.

Learning insight: HVAC cleaning work is never exempt, even when required for health or insurance purposes.

Why CRA Audits Duct Cleaning & Furnace Cleaning Businesses

Revenue Risks

• GST/HST not charged on duct cleaning packages
• furnace tune-ups billed without GST
• “air-quality testing” treated as exempt (it is taxable)
• sanitation fogging miscoded
• travel/service-call fees missing GST
• cash/e-transfer jobs underreported
• seasonal spikes not matching GST returns
• out-of-province vacation home contracts misrated
• multi-unit condos taxed inconsistently

Subcontractor Risks

• subcontracted technicians lacking valid GST numbers
• helpers paid cash without invoices
• T4A/T5018 mismatches
• no documentation for 2-tech crew jobs

ITC Risks

• missing invoices for:
– duct vacuums, negative-pressure machines
– HEPA filters, hoses & attachments
– disinfectants / sanitizing chemicals
– brushes, air whips, air snakes
– truck & trailer expenses
– PPE & respirators
• imported HVAC tools missing self-assessment (s.218)
• personal-use tools claimed
• ITCs overstated for home-storage/mixed-use space

Operational Risks

• no job logs
• ducts cleaned without formal invoices
• furnace/duct combined jobs not itemized
• supplier purchases too high for declared revenue
• commercial HVAC jobs lacking documentation
• dryer-vent add-ons not invoiced

High-risk operators:

• HVAC duct cleaners

• furnace cleaning companies

• commercial air-quality contractors

• subcontract-based duct teams

• hybrid HVAC + duct cleaning firms

Learning insight: CRA assumes underreported revenue + invalid ITCs + subcontractor issues unless proven otherwise.

CRA Duct-Cleaning Audit Process

1. CRA requests:
   – invoices (duct cleaning, furnace cleaning, sanitation, travel)
   – subcontractor invoices + GST numbers
   – equipment invoices (duct vacuums, hoses, HEPA units)
   – bank statements & e-transfer logs
   – job logs & daily schedules
   – vehicle mileage logs
   – ITC spreadsheets
   – disinfectant & chemical receipts
   – import records for HVAC tools

2. CRA tests:
   • GST/HST on all services
   • QC/ON/Atlantic tax-rate accuracy
   • subcontractor compliance
   • ITC validity & proof of payment
   • personal vs business tool/equipment use
   • job logs → deposits → GST filings
   • imported equipment self-assessment
   • proper billing of bundled furnace + duct jobs

3. CRA issues Proposed Audit Adjustment.

4. Mackisen CPA builds complete documentary + legal defense.

Learning insight: CRA reconstructs your entire season using job logs + equipment purchases + bank deposits.

Mackisen CPA’s Duct-Cleaning Audit Defense Strategy

• create a Duct-Cleaning Supply Tax Matrix (ducts, furnace, sanitation, travel, add-ons)
• rebuild GST/HST-compliant invoices
• validate subcontractor GST/HST numbers
• reconstruct ITC binder for equipment, tools, chemicals & trucks
• defend vehicle-use ITCs with mileage logs & allocation
• correct tax rates for multi-province HVAC work
• reconcile job logs → invoices → deposits → returns
• rebuild imported-equipment self-assessment
• prepare CPA-certified CRA audit binder
• negotiate penalty & interest reduction

Learning insight: Duct-cleaning audits are won through perfect logs, complete ITCs, valid subcontractor documentation.

Common CRA Findings in Duct-Cleaning & Furnace-Cleaning Audits

• GST/HST not charged on:
– duct cleaning
– furnace cleaning
– sanitation/fogging
– dryer-vent cleaning
– call-out & travel fees
• subcontractors unregistered
• ITCs denied for missing invoices
• imported vacuums/tools missing GST self-assessment
• bank deposits > reported sales
• mixed furnace/duct packages misclassified
• personal-use tools included in ITCs

Learning insight: CRA reassessments are primarily driven by invoice defects, missing ITCs, and subcontractor issues.

Real-World Results

• A duct-cleaning company avoided a $194,000 reassessment after Mackisen CPA rebuilt subcontractor compliance & job logs.
• A furnace-cleaning contractor reversed a $148,000 ITC denial with full equipment & chemical documentation.
• A commercial air-quality contractor eliminated penalties by correcting QC/ON GST rate logic.
• A dryer-vent cleaning operator cleared CRA findings through deposit→invoice→GST reconciliation.

Learning insight: CRA backs down when evidence is CPA-organized, job-mapped, and fully documented.

SEO Optimization & Educational Value

Primary keywords: GST/HST duct cleaning audit, CRA furnace cleaning audit, HVAC cleaning GST rules Canada, Mackisen CPA Montreal
Secondary keywords: duct ITC denial, subcontractor GST audit, dryer-vent GST/HST, HVAC sanitation GST

Learning insight: Air-quality and HVAC-cleaning audits have very high SEO demand due to rapid growth in the sector.

Why Mackisen CPA Montreal

With 35+ years defending duct cleaners, HVAC cleaning firms, furnace service companies, and air-quality contractors, Mackisen CPA Montreal is Québec’s top authority in GST/HST HVAC-cleaning audits.
We understand equipment, chemical usage, subcontractors, seasonal patterns, and CRA methodology deeply.

Learning insight: Duct-cleaning audits require technical understanding + documentation discipline + subcontractor control — all strengths of Mackisen CPA.

Call to Action

If CRA is auditing your duct-cleaning, furnace-cleaning, air-quality testing, or HVAC sanitation business, contact Mackisen CPA Montreal immediately:

📞 514-276-0808
📧 info@mackisen.com
🌐 mackisen.com

Learning Conclusion:

A CRA GST/HST Duct-Cleaning & Furnace-Service Audit tests labour taxability, chemical/equipment ITCs, subcontractor compliance, job-log accuracy, and multi-province tax rules.
Mackisen CPA Montreal ensures full protection against reassessments