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

What Our Learners Say

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Frequently Asked Questions

Do I need prior experience?+
No prior experience required. You need good literacy/numeracy and basic IT skills.
What is the difference between the 3-Day Online DEA course and the 2-Day Weekend DEA course?+

Both courses cover exactly the same Level 3 Domestic Energy Assessor syllabus and lead to the same recognised qualification. The training materials, assignments, portfolio requirements and assessment criteria are identical.

The only difference is how the training is scheduled.

The comparison below shows the difference between the two delivery options.


3-Day Course (Weekdays)2-Day Course (Weekend)
DaysMonday – WednesdaySaturday – Sunday
Start Time9:30 am8:30 am
Finish Time3:30 pm5:30 pm
Daily Training Hours6 Hours9 Hours
Total Duration3 Days2 Days

As you can see, the weekend course has longer training days, allowing us to cover the same syllabus in just two days. No topics are omitted or shortened, and every learner receives the same training materials, tutor support and guidance.

Whichever option you choose, you'll complete the same assignments and portfolio before achieving the same recognised qualification.

If weekdays are difficult because of work or other commitments, the 2-day weekend course offers a convenient way to complete your training without taking time off.

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. 

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.