Urgent EPC Rating improvement from F to D


The potential incoming tenant would not take up the lease unless the EPC rating was a Band E or above and would not consider the property with any systems using R22.

An assessor attended site and a new EPC was produced. This assessment identified that the full height warehouse was conditioned for heating and cooling via an all air system comprising an air handling unit, gas fired boiler and external chiller. The boiler also served a separate air system to the offices.

The accurate EPC produced was an F141. We therefore needed to explore options to improve the EPC rating to an E or better.


The client required a report within a week.


The original EPC model was uploaded to the arbn consult platform which allowed us to immediately see all the original EPC assessor’s inputs from the file as the system unlocks the EPC model file.

The platform allowed us to assess each of the inputs entered by the original EPC assessor, comparing these against site data from the landlord’s agent. This audit identified that the original system type entered was incorrect and that the assessor had used a system with a far lower expected energy consumption than that which was installed.


Using the accurate EPC produced, the F141 was uploaded into arbn consult and simulations run which identified options to achieve an EPC rating of D91.

Without arbn consult, the assessor would have had to run a number of EPC improvement simulation packages manually and record results at each stage. They would then have had to research costings and the output report would have taken at least a day to complete.

But using arbn consult, we were able to select from a range of costed retrofit solutions manually before running multiple simulations in minutes.

Summary of Benefits

arbn consult’s functionality meant that the report, costings and all options available to the landlord were quickly and efficiently delivered in a single document.

arbn consult ensured that the landlord’s interests were protected, that they were not at future risk under MEES regulations and were able to complete a ten-year lease on a previously empty building.

In summary, the project :

  • Quickly identified accuracy issues with the original EPC.
  • Simulated fully costed retrofit options to improve the EPC from an F141 to a D91.
  • Provided an intuitive investment report with costs, energy savings and ROI.
  • Provided a fast turnaround allowing lease negotiations to be satisfactorily completed.

MEES Advice

arbn consult is designed specifically for those providing MEES advice. It allows you to quickly and efficiently produce fully costed bespoke retrofit recommendations with Return on Investment and MEES 7-year payback calculations.

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