April 27, 2026
TM44 vs F-Gas: What’s the Real Difference and Why You Might Need Both in 2025 & 2026
October 10, 2025
Two certificates, one big confusion!
If you manage or own a building with air-conditioning, you’ve probably heard about TM44 inspections and F-Gas testing, and you might even assume they’re the same thing. They’re not.
In 2025, the UK is entering a new era of energy and environmental enforcement. Trading Standards and the Environment Agency are stepping up inspections, and the fines are increasing. Yet thousands of businesses remain unaware that F-Gas compliance doesn’t cover TM44, and that skipping either could cost thousands in penalties.
Both certificates are legal requirements, but they serve completely different purposes:
- TM44 focuses on energy efficiency and system performance.
- F-Gas focuses on environmental protection and refrigerant leak prevention.
If your building has air-conditioning systems totalling more than 12 kW, there’s a strong chance you need both. Here’s everything you need to know to stay compliant and efficient in 2025.
What Is a TM44 Inspection?
A TM44 inspection is required under the Energy Performance of Buildings (EPB) Regulations. It applies to all non-domestic and public buildings with combined air-conditioning output greater than 12 kW.
You must complete a TM44 inspection every five years using an accredited TM44 assessor.
What a TM44 includes
A professional inspection reviews:
- Energy performance and overall system efficiency
- Sizing and suitability of units for the building
- Control systems and temperature management
- Maintenance and usage patterns that cause wasted energy
- Opportunities for upgrades or replacements
👉 After assessment, you receive a TM44 report and an official certificate lodged with the government’s Landmark Register.
A valid TM44 certificate provides:
✅ Legal compliance proof for audits and lease renewals
✅ Lower operating costs through improved efficiency
✅ Support for EPC and MEES performance ratings
✅ Credibility in sustainability and ESG reporting
Over 80 % of UK buildings that require a TM44 certificate are still non-compliant as of 2025 — according to national data used in the TM44.uk market analysis.
👉 Learn more about our TM44 Air-Conditioning Inspection service.
What Is an F-Gas Inspection?
An F-Gas inspection is a legal requirement under the Fluorinated Greenhouse Gases (F-Gas) Regulations. These inspections ensure your air-conditioning systems do not leak refrigerants that contribute heavily to global warming.
Unlike TM44, which focuses on energy efficiency, F-Gas inspections focus on environmental safety.
What engineers check
- Leak detection and system integrity
- Pressure and refrigerant quantity
- Labeling and logbook accuracy
- Safe recovery, recycling, and disposal of gases
- Maintenance schedules in line with gas weight thresholds
Frequency:
- Every 3 months for large systems
- Every 6 months for medium systems
- Every 12 months for smaller systems
Only Refcom-registered or City & Guilds qualified engineers can carry out these inspections.
Failure to comply can lead to fines up to £5,000 per system, or prosecution in severe cases.
👉 Find details on our F-Gas Leak Testing & Compliance service.
TM44 vs F-Gas: Understanding the Difference
TM44 inspections aren’t just about avoiding fines. They also deliver tangible savings.
| Feature | TM44 Inspection | F-Gas Inspection |
|---|---|---|
| Legal Basis | Energy Performance of Buildings Regulations | F-Gas (Fluorinated Greenhouse Gas) Regulations |
| Purpose | Assess energy efficiency & performance | Prevent refrigerant gas leaks |
| Focus | Energy use, control, system design | Environmental protection & leak control |
| Frequency | Every 5 years | 3–12 months |
| Enforcement | Trading Standards | Environment Agency / DEFRA |
| Inspector Type | TM44-accredited energy assessor | Refcom-certified engineer |
| Outcome | TM44 report + lodged certificate | Leak test report + logbook |
| Penalty | £800 + fines in 2025 | Up to £5,000 per system |
Both inspections apply to the same physical equipment but cover different compliance goals.
Think of TM44 as your AC’s MOT for energy efficiency, and F-Gas as its emissions test. Both keep your system legal and responsible.
If you’re missing either, your air-conditioning setup is incomplete from a compliance standpoint.
Why You Might Need Both in 2025
The government’s 2025 crackdown is pushing commercial building owners to take compliance seriously.
- TM44 fines have risen from £300 → £800.
- Trading Standards now run cross-checks with the Landmark Register.
- The Environment Agency has expanded enforcement of F-Gas records and engineer qualifications.
This dual enforcement means skipping one inspection can trigger questions about the other.
The two certifications also align with the UK’s Net Zero 2050 targets:
- TM44 cuts wasted electricity by improving system efficiency.
- F-Gas reduces greenhouse-gas emissions from refrigerants.
Together, they form a complete building energy and environmental compliance strategy.
👉 Read more in our detailed report: The 2025 TM44 Non-Compliance Crackdown & UK Fines.
Common Myths That Cost Businesses Thousands
❌ “We just did our F-Gas test, so we’re compliant.”
✅ TM44 and F-Gas are separate laws with separate reports. You need both.
❌ “Our building is too small to qualify.”
✅ Even multiple split units that add up to 12 kW total output require TM44.
❌ “Our maintenance contractor covers it.”
✅ Only qualified TM44 assessors and Refcom engineers can legally issue certificates.
Don’t wait until Trading Standards call.
👉 Request a free compliance check to confirm whether your property needs both inspections.
How Combined TM44 + F-Gas Visits Save Time & Money
Many facilities book the two inspections separately — paying twice for site access, engineer time, and reporting.
With TM44.uk, both can be completed in one coordinated visit:
| Option | Number of Visits | Average Cost |
|---|---|---|
| Separate TM44 + F-Gas | 2 | £900 – £1,100 |
| Combined Visit | 1 | £650 – £850 |
Benefits of combining
- One appointment, one invoice, less downtime
- Unified reporting and advice
- 24–48 hour turnaround
- Access to multi-site portfolio management
Our Portfolio TM44 Management service handles recurring reminders and multi-building scheduling, ideal for landlords, retail chains, and property managers.
Energy & Environmental Benefits
Beyond legal compliance, combining both inspections delivers measurable value:
🌱 Reduced Energy Use – TM44 identifies control inefficiencies, reducing running costs by up to 30 %.
🌍 Lower Carbon Emissions – F-Gas ensures zero refrigerant leaks.
💡 Better Sustainability Scores – Improves EPC and MEES ratings.
📈 Enhanced Asset Value – Certified, efficient systems attract tenants and buyers.
Compliance isn’t just ticking boxes it’s active participation in the UK’s energy-efficiency mission
👉 Explore more about post-inspection upgrades in our Energy Efficiency Upgrade Report (Post-TM44).
What Happens If You Ignore Them
Ignoring these inspections can trigger a chain of expensive problems:
- £800 + TM44 fines from Trading Standards
- £5,000 + F-Gas fines per system
- Re-inspection orders and disruption
- Loss of insurance validity
- Barriers to leasing or selling properties
- Damage to your ESG credibility
The government plans to make TM44 and F-Gas compliance publicly visible through the Landmark Register, meaning non-compliance could soon be searchable by clients, tenants, or investors.
👉 If you’re at risk, our Emergency TM44 – 24/48-Hour Service can fast-track your certification before enforcement hits.
How TM44.uk Keeps You Fully Covered
At TM44.uk, we handle the full process:
✅ Nationwide coverage – engineers in every major UK city
✅ Accredited assessors & Refcom-registered partners
✅ 48-hour report turnaround
✅ Official government lodgement
✅ Bundled discounts for TM44 + F-Gas + MEES compliance
Our process is transparent, fast, and fully insured. Whether you operate a single office or a national portfolio, we deliver compliance without complexity.
👉 Book your combined TM44 + F-Gas inspection now and stay one step ahead of 2025 regulations.
Both TM44 and F-Gas are cornerstones of the UK’s evolving building compliance framework. One protects energy efficiency, the other protects the environment; together, they protect your business.
As enforcement rises, these certificates will soon become standard in due diligence for leases, audits, and ESG reporting. Don’t risk being part of the 80 % still unprepared.
Stay legal, save energy, and protect your reputation.
💬 Top 10 FAQs for “TM44 vs F-Gas: What’s the Real Difference
✨ “F-Gas and TM44 inspections aren’t just about ticking compliance boxes — they’re about future-proofing your building and protecting your bottom line. By combining both assessments, you reduce energy waste, prevent costly refrigerant leaks, and build a greener reputation for your business. Every compliant system means lower energy bills, longer equipment life, and proof that your company takes sustainability seriously — not just for 2025, but for the years ahead.” ✨
