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House Extension Calculations

Notional Dwelling Fabric Energy Efficiency

House Extension Calculations

THE BRIEF

THE PROCESS

  • To achieve compliance, the proposed extension must improve the performance of the dwelling
  • Our assessors specified a low U-Value Design and the installation of an efficient heating system

THE RESULTs

  • SAP RESULTS

≤ 29.41

Notional Dwelling Emission Rate (DER)

≤ 116.04

Notional Dwelling Fabric Energy Efficiency (DFEE)

28.89

Proposed Dwelling Emission Rate (DER)

116.03

Proposed Dwelling Fabric Energy Efficiency (DFEE)

PASS

PASS

  • Compliant

  • The proposed dwelling is more efficient than the notional dwelling therefore compliant with the Part L Building Regulations

Please refer to our Myth Busters for SAP Calculations here for common misconceptions

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