Update: RdSAP conventions v10.0 announced

The Department for Communities and Local Government (DCLG) has announced a revised set of RdSAP conventions (v10.0).

From 31st December 2017, the new and amended RdSAP conventions, which apply to assessments in England and Wales only, must be applied by all RdSAP accredited energy assessors when producing Energy Performance Certificates (EPCs) for existing dwellings.

In order to manage the implementation process successfully, accreditation schemes, energy assessors and training providers must also apply the ‘new’ conventions on the same date.

Update: RdSAP conventions v10.0 announced

For audit and management purposes, the conventions must be applied on the dates shown in the 'Implementation Date' column on the right-hand side of the conventions table (new or changed conventions go live on 31st December 2017).

These conventions will be included as part of future quality assurance checks of the assessments that have been undertaken and the EPCs produced thereafter.

What are the changes in RdSAP conventions v10.0?

Version 10 of the conventions are mostly minor text changes, or structure changes to make the conventions more logical.

Listed below are most of the key areas which have been updated:

  • 1.01 - Use of RdSAP
  • 1.04a - Self-contained dwelling attached to or forming an extension of another building

2. Measurements and geometry

  • 2.01 - Measurements
  • 2.02 - Precision of lengths
  • 2.03 - Sheltered wall length (unheated corridors)
  • 2.04a - Habitable room count
  • 2.04b - Heated habitable room count
  • 2.06 - Roof rooms / Attics (whether to include in the assessment and rules for detailed measurements)
  • 2.13 - Alternative wall
  • 2.14 - Definition of a “window”
  • 2.15 - Window area
  • 2.18 - Dimensions
  • 2.22 - Wall thickness (per building part)
  • 2.24 - Party wall lengths
  • 2.25 - Private access stairwell to a single dwelling (e.g. access to upper flats in four in a block dwelling)

3. Construction and insulation

  • 3.02 - System build type
  • 3.03a - “As built” insulation category (walls, floors, roofs)
  • 3.03b - “Unknown” insulation type (walls, floors, roofs)
  • 3.03c - “Unknown” insulation thickness
  • 3.04 - Access to loft insulation and rafter insulation
  • 3.07 - Insulation thickness
  • 3.12a – Glazing age
  • 3.12b – Glazing gap

4. Main heating

  • 4.01b – Design flow temperature for condensing boilers and heat-pumps
  • 4.03 – Boiler missing or not working
  • 4.09 – Two main systems
  • 4.17 – Time and Temperature Zone Control (TTZC)
  • 4.18 – Central heating pump age

5. Secondary heating

  • 5.01 – Secondary heating

6. Water heating

  • 6.04 – Separate boiler or heat pump for DHW
  • 6.05 – Enclosed hot water cylinders and insulation of hot water cylinders
  • 6.06 – Hot water thermal store

9. Miscellaneous

  • 9.06 – Flue gas heat recovery
  • 9.08 – Waste water heat recovery
  • 9.13 – Electricity meters

Download RdSAP conventions v10.0

The revised set of conventions can be found in your member’s area. The sections highlighted in blue are the new/amended conventions which must be applied from the 31st December 2017.

Download the latest RdSAP conventions v10.0.

For further guidance, we will be releasing a RdSAP Technical Bulletin to explain the changes in detail. The RdSAP Manual will also be revised to reflect the new conventions.





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