According to the WELL Certification Guidebook, performance verification requires at least 50% occupancy of the project area, unless otherwise approved by IWBI. This is to ensure that the testing reflects the actual conditions and performance of the building when it is in use. Therefore, the project team should inform the developer that they cannot schedule performance verification until the occupancy requirement is met.
References:
* WELL Certification Guidebook, page 17, section 3.2.3: Performance Verification
* WELL v2 | Certification Process | IWBI, Step 3: Performance Verification