History of RdSAP

It is now 10 years since RdSAP was officially recognised by Government. The EU ‘Energy Performance of Buildings Directive (EPBD)’ forced member states to implement laws to reduce energy use in buildings across Europe.

The 2 articles that drove Energy Performance Certificates forward were the following:

Article 7 “...when buildings are constructed, sold or rented out, an energy performance certificate is made available to the owner or by the owner to the prospective buyer or tenant…”

Article 10 “the certification of buildings…are carried out in an independent manner by qualified and/or accredited experts..”

Elmhurst as leading experts in the field of energy assessment of domestic dwellings were contacted early to help lead the development of an appropriate methodology and framework. The Government (DEFRA) contracted the Federation of Authorised Energy Rating Organisations (FAERO) and the BRE to develop a standardised methodology.

FAERO contained MVM Starpoint (were then Northgate, now purchased by Elmhurst), NES & Elmhurst Energy who already had proprietary SAP energy rating systems. Elmhurst for example had trained all the Charted Surveyors in the UK, who could offer ‘home energy reports’ with home buyers reports depending on the lenders requirements.  The EU directive required a ‘common approach’ for a member state and as such FAERO came together to produce Reduced Data SAP (RdSAP).

  • Phase 1 – compared different data sets and inference rules, agree a standard approach
  • Phase 2 – tested the agreed approach; sensitivity, can we do without any data items?
  • Phase3 – revisions arising from Phase 2; non standard data collection; integration with the HCR data collection; comparisons with new build SAPs
  • Phase 4 – Energy Report design; design a report that homebuyers will trust, and define how to determine the suggested improvements
  • Phase 5 – define the Quality Assurance Requirements
  • Phase 6 – technical field trials and consumer field trials Technical Field Trials – Summer 2004, 15 Inspectors (who took part in the HCR trials), 20 different dwellings in different locations in UK.


Example Report as part of Home Condition Report: (Note section H. Right at the back!)

Energy Performance Certificate

A later version, which is more like the standalone EPC with the 2 graphs:

Energy Performance Report

Page 2: 

Energy Performance Report Page 2

In terms of implementing laws and regulations the Office of the Deputy Prime Minister (ODPM) now Communities & Local Government (CLG) took the lead in England &Wales. DFPNI were closely monitoring this for Nortern Ireland and Scottish Buildings Division and the Scottish Government looked at how to implement in Scotland. In fact in Scotland, Elmhurst trained all the chartered surveyors involved in the Single Survey Pilot back in 2004, this successful trial started the transition to this policy.

Elmhurst’s expertise in this sector continues, we have been heavily involved in all the amendments and changes to the EPC and RdSAP methodology from the start, and there have been many! It is now a very different methodology from the start, but at its heart it is still a measuring tool to compare and contrast domestic dwellings to enable consumers to understand how energy efficient the property is and to give people the opportunity to understand how they can improve the energy performance of their home.  We at Elmhurst value our history but ensure that we build upon it to  always be at the cutting edge of this fast moving industry.

Stuart Fairlie – Head of Technical, Elmhurst Energy

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