Class 2: Updating a NatHERS assessment

Region: All States

I’ve been asked to update the NatHERS assessments for 229 Class 2 apartments. I did not do the original assessment. The Building Surveyor has said the below to the client in relation to v4.3 of BERS being used.  Can you please confirm that it is ok for me to redo the NatHERS assessments using BERS v4.3 and Chenath v3.13b engine. 

TPA Support Response:

• The overall understanding of regulatory compliance is that the metrics that are current at the time that substantial design decisions are being made for a project should remain in place for assessing final completion adequacy.
• This is to ensure that changes in regulations or metrics do not trigger substantial redesign or specification amendment mid-way through the procurement process.
• That understanding can however be complicated if the project suffers unusually long delays.
• It is usually considered that compliance stringency is raised over time and accordingly new metrics are acceptable for reassessment to confirm minimum standards.
• Using a new/current version will normally be totally acceptable with regard to compliance but may not meet approval by the proprietor if it results in amended higher level specification than the earlier version.