You do not apply directly to the BER database. Instead, arrange a BER assessment with an SEAI-registered BER assessor, who will inspect the property and submit the assessment to SEAI for certification and listing. You can find an assessor through the official SEAI website, while existing certificates can usually be checked on the public BER register using the property details. The assessor will explain the likely cost and any documents needed, and SEAI ultimately determines the published BER rating.