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.

Expert Tutors
Learn from industry professionals
Flexible Learning
Classroom, online live & guided learning
Practical Support
Assignments & portfolio guidance included
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Ongoing Portfolio Support
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Industry-recognised UK qualification
Experienced Tutors
Taught by working assessors
Online Learning Materials
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Portfolio Support
Hands-on assignment guidance
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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

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.

Do I Need Previous Construction Experience?+
Not necessarily. Previous experience in construction, surveying, engineering or property can be helpful, but it is not always required. You will still need to complete the appropriate Non-Domestic Energy Assessor qualification and demonstrate the required competence. Relevant industry experience may allow some learners to follow a faster training route or receive recognition for prior learning. Entry requirements vary, so check the requirements of the specific course before enrolling. 
Do you issue hard copy certificates?+

Awarding organisations now issue digital certificates for most qualifications, which are widely accepted by employers, accreditation schemes and other organisations throughout the UK.

Your digital certificate is secure, easy to store and can be downloaded and shared electronically whenever proof of your qualification is required.

If you would like a professionally printed hard copy, we can arrange this for an additional fee. Once your qualification has been fully signed off, you'll receive a sign-off email containing details of how to request a printed certificate and the applicable postage and administration charges.

If an official hard copy certificate is available from the awarding organisation, we'll provide you with all the available options in your sign-off email, allowing you to choose the option that best suits your needs.

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.