0203 488 2554 training@ozonegroup.co.uk

Build Your Career inEnergy Assessment & Building Compliance

City & Guilds approved training in Domestic EPCs, Retrofit, SAP, Non-Domestic Energy Assessment and more. Flexible learning. Expert tutors. Real-world support.

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Assignments & portfolio guidance included
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Industry-recognised UK qualification
Experienced Tutors
Taught by working assessors
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Featured Courses

Our most popular Energy Assessor qualifications

Why Ozone

Why Choose Ozone Training

We're working Energy Assessors who train new assessors — not a generic training company.

  • Run by practising DEAs since 2011
  • City & Guilds approved courses
  • Real-world tips, not just exam-pass content
  • Spread cost in interest-free instalments
  • 100% pass guarantee with free re-sits

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Frequently Asked Questions

Is a Commercial Energy Assessor the same as a Non-Domestic Energy Assessor?+
Yes. The terms are commonly used to describe the same profession. Non-Domestic Energy Assessor is the formal industry title, while Commercial Energy Assessor is often easier for customers to understand.
Can I pay for my course in instalments? How does the payment plan work+

Yes. We offer flexible interest-free payment plans on most of our training courses, making it easier to spread the cost of your qualification.

To secure your place, you'll pay an initial deposit when you book your course. The remaining balance (including VAT) is then divided into two equal monthly instalments.

Your instalments are due on the same date in each of the following two months after your initial payment. For example, if you pay your deposit on the 10th of the month, your remaining payments will be due on the 10th of each of the next two months.

There are no hidden charges or interest when payments are made as agreed. We'll confirm your payment schedule before your course starts, so you'll know exactly when each instalment is due.

If you have any questions about our payment plans or need help choosing the option that's right for you, our team will be happy to assist before you enrol.

How long does it take to qualify after completing the Domestic Energy Assessor (DEA) course?+

The time it takes to achieve your Level 3 Domestic Energy Assessor qualification depends on the training option you choose and how quickly you complete your portfolio.

Classroom Courses:
If you attend one of our classroom-based Domestic Energy Assessor courses and have completed all the required assignments before or during the course, your portfolio can often be reviewed and signed off during the classroom session itself. This is the fastest route to qualification for learners who arrive fully prepared.

Online Courses:
For our online training, you complete your portfolio after your live online sessions. Most learners who dedicate 2 to 3 hours per day to their assignments can realistically complete everything within around one week. Once your portfolio has been submitted, your assessor will review your work and provide feedback where required. If any amendments are needed, you'll receive clear guidance and can resubmit your work.

There is no fixed deadline to complete your portfolio within your course access period, so you can work at a pace that suits your schedule. However, learners who stay engaged and complete a little each day typically qualify much sooner.

Our aim is not simply to help you pass the course, but to ensure you leave with the knowledge, practical skills and confidence to carry out domestic Energy Performance Certificates (EPCs) professionally from day one.

Ready to start your DEA career?

Speak to our team or book your course today. We'll guide you from enrolment to your first paid EPC.