Please note that DECC have suspended the requirement for cost effectiveness tests for individual metering and removed the Heat Metering Viability Tool. DECC have posted the following notice on the webpage that hosts the heat networks metering guidance and regulations (Heat Networks Metering and Billing: compliance and guidance - Detailed guidance - GOV.UK):

“The European Commission is developing guidance on the application of cost effectiveness tests for heat metering, under the Energy Efficiency Directive. This means that the earlier DECC cost effectiveness tool will need to be revised. In most properties, the tool had indicated that individual heat meters will not be cost-effective. Therefore, pending the revision of the tool we are advising that no further assessments should be undertaken. Any assessments which are undertaken following this announcement using the current tool may need to be redone once the revised tool has been introduced. The requirement to install heat meters to measure final consumption of heat from a heat network in buildings occupied by one final customer will not be enforced by the National Measurement and Regulation Office pending revision of the tool. The remaining requirements in the regulations are unaffected (for example in relation to building-level meters and newly constructed buildings connected to a district heating network and those buildings on district heating networks that undergo a major renovation). The remaining notification requirements still apply."