February 2, 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
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1️⃣ Do I need both TM44 and F-Gas inspections for my building?
Yes. TM44 and F-Gas inspections are two separate legal requirements. TM44 checks your system’s energy efficiency, while F-Gas ensures no refrigerant leaks. If your combined cooling capacity exceeds 12 kW and you use refrigerant gases, you legally need both.
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2️⃣ What is the main difference between TM44 and F-Gas compliance?
TM44 is about energy performance and efficiency, required every 5 years under the Energy Performance of Buildings Regulations.
F-Gas focuses on environmental safety preventing gas leaks and protecting the ozone layer and is required every 3–12 months, depending on system size. -
3️⃣ Who enforces TM44 and F-Gas regulations in the UK?
TM44 is enforced by Trading Standards under the Department for Levelling Up, Housing and Communities.
F-Gas compliance is enforced by the Environment Agency and DEFRA. Both bodies can issue significant fines for non-compliance. -
4️⃣ How often do I need to carry out F-Gas leak tests?
It depends on the refrigerant gas charge:
Small systems: every 12 months
Medium systems: every 6 months
Large systems: every 3 months
Your engineer will confirm the correct schedule during your F-Gas Leak Testing & Compliance visit.
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5️⃣ What happens if I ignore TM44 or F-Gas inspections?
Ignoring either can result in fines, enforcement notices, and reputational damage.
TM44 penalties are now £800 per building, while F-Gas violations can exceed £5,000 per system.
Your property may also lose insurance coverage or leasing eligibility if non-compliant. -
6️⃣ Can I combine TM44 and F-Gas inspections in one visit?
Absolutely. TM44.uk offers combined TM44 + F-Gas inspections, reducing cost and downtime.
One visit covers both energy and environmental compliance, and you receive both reports within 48 hours. -
7️⃣ Who can perform a TM44 inspection or F-Gas test?
A TM44 inspection must be completed by an accredited TM44 energy assessor.
An F-Gas test must be done by a Refcom-certified engineer.
At TM44.uk, we partner with both qualified professionals to handle national coverage in a single coordinated visit. -
8️⃣ How do TM44 and F-Gas help with energy efficiency and sustainability?
TM44 identifies inefficient controls and oversized systems, helping cut energy waste by up to 30–40%.
F-Gas prevents refrigerant leaks, which can have 1,000+ times the warming potential of CO₂.
Together, they make your building greener and more cost-efficient. -
9️⃣ Where can I check if my TM44 certificate is valid?
You can search the government’s Landmark Register to confirm if your TM44 certificate is active and valid. If no record appears, you likely need a new inspection book one here.
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🔟How much do TM44 and F-Gas inspections cost in the UK?
Typical prices vary based on building size and system complexity:
TM44 inspection: from £450 + VAT
F-Gas testing: from £150 + VAT
Combined packages start at £650, including both reports and government lodgement.
👉 Get a free quote today.
✨ “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.” ✨
