Become a CIBSE Certification ESOS Lead Assessor

What is ESOS? Read updates and news about the scheme.

The ESOS regulations require that ESOS Lead Assessors be sourced from approved existing schemes run by professional bodies, such as the CIBSE Certification Low Carbon Consultants register. Therefore CIBSE Certification ESOS Lead Assessor applicants are required to be registered as a CIBSE Certification Low Carbon Consultant.

ESOS registration consists of two stages.

Stage 1. Register as a CIBSE Certification Low Carbon Consultant (LCC) if not yet registered

Choose which LCC strand you wish to join and pass the relevant LCC assessment.  There are no formal entry requirements, but it is advised that candidates familiarise themselves with the level of knowledge and experience (at least two years) expected beforehand and take appropriate training if required.

Visit CIBSE Training for more details and a list of upcoming LCC course dates.

Once you have passed the LCC exam, complete the LCC application process

Stage 2. Register as a CIBSE Certification ESOS Lead Assessor

Successfully complete an ESOS Lead Assessor training course and exam.  Visit for more details and a list of upcoming training dates.

1. Once you have passed the exam, download the ESOS Lead Assessor application pack
2. Complete the application form ensuring you and your referee have signed the form
3. Submit a copy of your employer's Professional Indemnity Insurance (PII) document
4. Submit a CV detailing your experience in energy improvement related work
5. List your area(s) of specialisms

Email the completed application form and supporting documentation to CIBSE Certification at