SEAI grants are paid after the works are complete, inspected where selected and the claim documentation is submitted. You must have grant approval before starting, and you fund the works in the meantime.
Approval must be in place before any works start. Works carried out before approval are not eligible, even if they would otherwise qualify, so do not let a contractor begin on the promise that paperwork will follow.
After completion you submit the declaration of works, contractor documentation and the post-works BER where required. SEAI carries out inspections on a sample of jobs, and payment issues once the claim is validated.