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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500+ Learners Trained in Just Last Year
Ongoing Portfolio Support
City & Guilds Approved Centre
Industry-recognised UK qualification
Experienced Tutors
Taught by working assessors
Online Learning Materials
Comprehensive study resources & portal access
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

What happens after I purchase a course?+

Once you've booked your course, we'll guide you through every step of the process, making your learning journey as smooth and straightforward as possible.

Immediately after your purchase, you'll receive a confirmation email containing your booking details. Please check your inbox and your junk or spam folder, as confirmation emails can occasionally be filtered by your email provider.

The confirmation email will also contain a secure link to complete your enrolment. You'll be asked to upload any required documents so we can process your registration and prepare your course. Completing your enrolment as soon as possible helps us ensure everything is ready before your training begins.

If you've booked an online or self-study course, you'll also receive access to our Student Assessment Management System (SAMS), where you'll find your learning materials, assignments and course resources.

Before your course starts, we'll send you everything you need, including your course schedule, joining instructions and any preparation required. For online courses, you'll receive details of how to join your live training sessions. For classroom courses, we'll provide the venue information and everything you need for the day.

Once your training has been completed, you'll work through your assignments and portfolio. Your tutor will review each submission, provide feedback where necessary and sign off your work as you successfully complete each assessment.

After all of your assignments have been signed off, your portfolio is reviewed by our Internal Quality Assurer (IQA) as part of our quality assurance process. Once this has been completed, your qualification is claimed from the awarding organisation, and your certificate is typically issued within two weeks of the final sign-off.

After receiving your qualification, we'll guide you through the next steps, including joining an accreditation scheme, choosing any equipment you may need and preparing to start your career as a qualified Energy Assessor. Our support continues even after you've qualified, so you'll always have someone to turn to if you need advice or guidance.

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.

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.

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.