1. RdSAP Conventions Version 9.0 Quidos Quality Assurance & Technical Support

2. Contents  Introduction  What are the RdSAP Conventions?  Who decides on the Conventions?  New Conventions  Amended Conventions  What does this mean for DEAs?  Further information  Introduction  What are the RdSAP Conventions?  Who decides on the Conventions?  New Conventions  Amended Conventions  What does this mean for DEAs?  Further information

3. Introduction  A new set of RdSAP Conventions was released on 12 th August 2016 for implementation from 1 st October 2016  The Conventions must be followed by all Domestic Energy Assessors completing an RdSAP assessment on an existing dwelling  A new set of RdSAP Conventions was released on 12 th August 2016 for implementation from 1 st October 2016  The Conventions must be followed by all Domestic Energy Assessors completing an RdSAP assessment on an existing dwelling

4. What are the RdSAP Conventions?  Whilst all DEAs strive to ensure that the assessments they complete are as accurate as possible, the assumptions made by the calculation engine produce inherent inaccuracy.  The RdSAP Conventions provide a framework so that all assessors can make the same assumptions based on the circumstances of the property.  The Conventions equalise the knowledge base amongst assessors, allowing newer assessors to produce the same results as more experienced DEAs, with the same basic equipment.  Whilst all DEAs strive to ensure that the assessments they complete are as accurate as possible, the assumptions made by the calculation engine produce inherent inaccuracy.  The RdSAP Conventions provide a framework so that all assessors can make the same assumptions based on the circumstances of the property.  The Conventions equalise the knowledge base amongst assessors, allowing newer assessors to produce the same results as more experienced DEAs, with the same basic equipment.

5. Who decides on the Conventions?  The Conventions are drawn up and decided upon by a group which represents the industry as a whole:  BRE – Developers of the SAP/RdSAP specification;  DCLG/Scottish Government/BIES (formerly DECC);  Representatives from the Accreditation Bodies;  Representatives of the DEA organisations (IDEA/Alliance)  By being represented in the group, Quidos can put forward the opinions and concerns of our assessors and include this input in the drafting of Conventions.  The Conventions are drawn up and decided upon by a group which represents the industry as a whole:  BRE – Developers of the SAP/RdSAP specification;  DCLG/Scottish Government/BIES (formerly DECC);  Representatives from the Accreditation Bodies;  Representatives of the DEA organisations (IDEA/Alliance)  By being represented in the group, Quidos can put forward the opinions and concerns of our assessors and include this input in the drafting of Conventions.

6. RdSAP Conventions v9.0 should be used for all lodgements from: 1 st October 2016 The current Conventions (v8.1) will still be valid and used for auditing purposes until that date.

7. New Conventions This section will look at the full wording of the new Conventions

8. Convention 1.04b Not self-contained separate part of dwelling If there is a separate part of the dwelling which is not self-contained but contains rooms that are used as part of the main dwelling, e.g. bedrooms, study etc. in a large detached garage or outbuilding converted into part of the living accommodation of a main property: - if heated by the main heating system (as defined for the main dwelling), include in the assessment of the main dwelling and a single EPC for the main dwelling to be issued - otherwise omit from the assessment.

9. Convention 2.04b Heated habitable room count Includes all habitable rooms heated by either main heating system(s) or fixed secondary heating

10. Convention 3.03c Unknown insulation thickness This convention refers to unknown insulation thickness. “Unknown insulation thickness” should be used only in exceptional circumstances, such as: - conflicting evidence of insulation thickness (visual and/or documentary) - when you can see insulation present but cannot measure it

11. Convention 4.19 Heating controlled by mobile app Heating controls adjustable via a mobile app only, where there are no visible controls in the dwelling, are not included in the assessment, i.e. “no time or thermostatic control”.

12. Convention 6.08 Instantaneous water heater Disregard a small water storage volume. A ‘small’ volume means less than or equal to 55 litres; If the storage volume exceeds 55 litres, it is specified as an “electric immersion” or “gas boiler for water heating only”.

13. Convention 6.09 Electric shower If the only water heater is an electric shower, specify as “electric instant water heating”

14. Convention 1.04b  The purpose of this new Convention is to work with Convention 1.04a on which dwelling parts must be included in the overall assessment of the main property.  If a separate, but not self-contained, part of the dwelling is used as part of the main dwelling, and is heated by the defined heating system for the main dwelling, it must be included as part of that assessment.  The purpose of this new Convention is to work with Convention 1.04a on which dwelling parts must be included in the overall assessment of the main property.  If a separate, but not self-contained, part of the dwelling is used as part of the main dwelling, and is heated by the defined heating system for the main dwelling, it must be included as part of that assessment.

15. Convention 2.04b  The Convention is aimed at ensuring that the correct number of heated habitable rooms are included as part of the assessment of the dwelling.  DEAs must count all habitable rooms heated by either the main heating system and/or fixed secondary heating.  Portable electric heaters cannot be considered as these are not fixed heat emitters.  The Convention is aimed at ensuring that the correct number of heated habitable rooms are included as part of the assessment of the dwelling.  DEAs must count all habitable rooms heated by either the main heating system and/or fixed secondary heating.  Portable electric heaters cannot be considered as these are not fixed heat emitters.

16. Convention 3.03c  This new Conventions works in line with Conventions 3.03a and 3.03b in terms of defining and inputting insulation, specifically when the thickness of insulation is not known.  The use of “Unknown” as an insulation thickness must only be used in exceptional circumstances, such as:  Conflicting evidenced been the visual inspection and/or documentary evidence  When an assessor can visually inspect the insulation but cannot measure it  Some other Conventions may specify that DEAs use “Unknown” – these would still be applicable in this circumstance.  This new Conventions works in line with Conventions 3.03a and 3.03b in terms of defining and inputting insulation, specifically when the thickness of insulation is not known.  The use of “Unknown” as an insulation thickness must only be used in exceptional circumstances, such as:  Conflicting evidenced been the visual inspection and/or documentary evidence  When an assessor can visually inspect the insulation but cannot measure it  Some other Conventions may specify that DEAs use “Unknown” – these would still be applicable in this circumstance.

17. Convention 4.19  Technology is evolving whereby the traditional controls for heating systems are being surpassed by mobile technologies, however, this can be problematic in attempting to ascertain the means of control at the time of assessment  When a heating system is ONLY controlled through a mobile app, it must be considered as ‘No Time or Thermostatic Control’.  This convention will not cover Hive or Nest-type systems, which enable manual control without the use of a mobile app.  Technology is evolving whereby the traditional controls for heating systems are being surpassed by mobile technologies, however, this can be problematic in attempting to ascertain the means of control at the time of assessment  When a heating system is ONLY controlled through a mobile app, it must be considered as ‘No Time or Thermostatic Control’.  This convention will not cover Hive or Nest-type systems, which enable manual control without the use of a mobile app.

18. Convention 6.08  After feedback from assessors, Quidos proposed a new Convention to aid in the identification of instantaneous water heating systems. We are pleased that this has been included in this latest version.  A device with a water storage volume of less than, or equal to, 55ℓ shall be considered as an electric instantaneous water heater. These devices are typically found beneath, or above, a sink. Where the volume exceeds 55ℓ, it shall be recorded as an electric immersion, or a gas boiler for water heating only.  DEAs should ignore this device from the Hot Water Cylinder entry: ‘No Cylinder’  After feedback from assessors, Quidos proposed a new Convention to aid in the identification of instantaneous water heating systems. We are pleased that this has been included in this latest version.  A device with a water storage volume of less than, or equal to, 55ℓ shall be considered as an electric instantaneous water heater. These devices are typically found beneath, or above, a sink. Where the volume exceeds 55ℓ, it shall be recorded as an electric immersion, or a gas boiler for water heating only.  DEAs should ignore this device from the Hot Water Cylinder entry: ‘No Cylinder’

19. Convention 6.09  This final new Convention has been included to cover the very rare instances where the only water heating within a dwelling is from the electric shower.  In circumstances such as this, electric instantaneous water heating with no cylinder shall be recorded by the DEA.  This final new Convention has been included to cover the very rare instances where the only water heating within a dwelling is from the electric shower.  In circumstances such as this, electric instantaneous water heating with no cylinder shall be recorded by the DEA.

20. Review of new Conventions  The majority of the new Conventions are intended to support other Conventions where there was some areas of ambiguity.  Convention 4.19 (Heating control by mobile app) would be the most likely to be misinterpreted. There are very few heating systems which are solely-operated by a mobile app, and these are mostly electric radiators. DEAs should not confuse the Hive/Nest control systems with this and should continue to enter these as ‘Programmer & Room Thermostat’.  A cylinder will not need to be included where electric instantaneous water heating is included.  Always clarify any uses of “Unknown” within your site notes and data collection sheets.  The majority of the new Conventions are intended to support other Conventions where there was some areas of ambiguity.  Convention 4.19 (Heating control by mobile app) would be the most likely to be misinterpreted. There are very few heating systems which are solely-operated by a mobile app, and these are mostly electric radiators. DEAs should not confuse the Hive/Nest control systems with this and should continue to enter these as ‘Programmer & Room Thermostat’.  A cylinder will not need to be included where electric instantaneous water heating is included.  Always clarify any uses of “Unknown” within your site notes and data collection sheets.

21. Amended Conventions This section will highlight only the amended text within the existing Convention wording. DEAs should review all the relevant text in the full Conventions document. This section will highlight only the amended text within the existing Convention wording. DEAs should review all the relevant text in the full Conventions document.

22. Convention 1.04a Self-contained dwelling attached to or forming an extension of another building A property can have an additional building unit (e.g. an ‘annexe’) which, if it is self-contained, and meets the dwelling definition of building, needs to have its own EPC. The annexe may share a party wall(s) with the main dwelling. Standalone buildings (i.e. physically separate from the main building) with a total useful floor area of less than 50 m² do not require an EPC. A building unit designed or altered for separate, self- contained use could be indicated by the accommodation having its own cooking and bathing facilities and its own access (from the outside, or via a communal corridor, without having to enter via the main dwelling), and may have separate or shared provision of heating and ventilation, but with the ability by the occupier of each dwelling to independently control those services. An example might be a self-contained flat in a building. If the ‘annexe’ is not self-contained and is heated by the main system serving the main dwelling, assess as part of the main dwelling.

23. Convention 2.03 Sheltered wall length (unheated corridors) Where the sheltered wall extends over more than one building part, e.g. it extends across the main building and an extension, assign the sheltered wall length to the building part with the longer sheltered wall and deduct the relevant amount from the heat loss perimeter of the other. Example: total unheated corridor length is 10m of which 2m is in the main building part and 8m in the extension. Record the extension as having the sheltered alternative wall of length 10m, increase the heat loss perimeter of the extension by 2m and deduct 2m from the heat loss perimeter of the main dwelling.

24. Convention 2.04a Habitable room count If a conservatory is open to the rest of the dwelling it is NOT counted as a separate room.

25. Convention 2.13 Alternative walls Disregard an alternative wall when less than 10% of total exposed wall area of the building part (including windows and doors) unless documentary or visual evidence exists of different retrofitted insulation either of the alternative wall or of the remaining wall in the building This does not apply to a sheltered wall; treat a sheltered wall as an “alternative wall” and always include it, even when its area is less than 10% of total exposed wall area.

26. Convention 3.03b “Unknown” insulation type This convention refers to unknown insulation type, not unknown insulation thickness. Do not use the “unknown” option for insulation inappropriately as this automatically suppresses any insulation recommendation.

27. Convention 3.04 Loft insulation and rafter insulation If loft insulation is fully obstructed (e.g. boarded or obscured by items stored) enter “pitched, access, loft insulation unknown” unless householder has documentary evidence (maximum thickness is depth of joists) or lifts the boards or removes the obstructions. If the property has multi-foil or foam insulation at joists or rafters, see convention 3.07. Partly obstructed lofts are treated as follows: o <= 25% obstructed: treat as not obstructed and record thickness of visible insulation o > 25 to 75%: divide into extensions o > 75%: treat as fully obstructed

28. Convention 3.06 Internal wall lining (creating an airspace behind) Dry-lining alone does not confirm the presence of insulation.

29. Convention 3.07 Insulation thickness If insulation is multi-foil, the thickness is entered as twice its actual thickness. Any foam-type insulation can be doubled in thickness if there is documentary evidence of the type of insulation and manufacturer’s information that the lambda-value (thermal conductivity) is less than 0.025.

30. Convention 3.08 U-value entry (walls, roofs, floors) The U-values of existing elements (walls/roofs/floors, etc.) must be the RdSAP default values (e.g. entered “as built”) and not overwritten unless specific documentary evidence of the thermal conductivity of the individual materials of the building element of the property being assessed is provided and was undertaken in accordance with BR 443 “Conventions for U-value calculations” (BRE, 2006). Evidence of suitable expertise and experience can be demonstrated by, but is not limited to, membership of a recognised U-value calculation competency scheme or OCDEA or Level 4 non- domestic energy assessor membership, or any other process recognised by Accreditation Schemes/Approved Organisations and Government

31. Convention 3.12 Glazing age If no evidence available from the above sources (date on spacer bar or frame, or documentary evidence such as a FENSA certificate or manufacturer guarantee), use the building age as the default. An image showing the gap between panes is not sufficient to infer glazing age.

32. Convention 3.13 Age band for roof room Same as the building part unless evidence proves otherwise. Evidence includes documentary evidence (e.g. planning applications), dated photographs of the property concerned validating date of construction (the evidence might establish the earliest possible date of construction if roof room is absent in the photograph).

33. Convention 3.15 Glazing gap This is the width of the spacer bar between the two panes of glass. It is required for windows with PVC frames pre 2002 or unknown when that is the most prevalent type of window. Where a mixture of glazing gaps are present, all window areas should be measured. (Much more than typical)

34. Convention 4.03 Boiler missing or not working If boiler/heating system is fitted/installed but not working (or condemned) it should still be entered as the main heating system. If boiler not fitted/installed but intended – enter no heating system.

35. Convention 4.09 Two main systems If second main heating system is used only for domestic hot water see 6.04. Main systems 1 and 2 cannot be room heaters except in the case of the dwelling’s heating consisting solely of room heaters. When there are two main systems, o system 1 always heats the living area; o when both systems heat the living area, main system 1 is the one that heats the most habitable rooms; o when both systems heat the same number of habitable rooms; main system 1 is the system that provides water heating; o when neither or both main heating systems heat water, main system 1 is the system which is cheapest to run (fuel cost from SAP Table 12 divided by the efficiency of heating system). If there are more than two main heating systems, use the rules above for determining main systems 1 and 2 and disregard the third.

36. Convention 4.13 TRVs Include when on 50% or more of the radiators. For this purpose include all radiators including those not in a habitable room (e.g. in a hallway).

37. Convention 4.14 Electric heating appliances Treat electric underfloor heating mats and infra-red heaters as “electric panel heaters”.

38. Convention 7.01 Lights Include only fixed fittings. The number of light fittings is counted (not the number of bulbs, e.g. a chandelier is one fitting).

39. Convention 9.02 Documentary evidence Acceptable documentary evidence includes, but is not limited to, official letters from the applicable Registered Social Landlord (RSL) or certificates, warranties, guarantees. The assessor must be confident, and able to demonstrate, that any documentation relates to the actual property being assessed and that there is no physical evidence to the contrary. Evidence of intent to install does not qualify as acceptable documentary evidence.

40. Convention 9.05 Photovoltaics If the kWp cannot be ascertained, do not allocate the PV, except where it is connected to a meter serving a single dwelling. Where the meter is serving a single dwelling, record the percentage of the total roof area occupied by PVs. The total roof area includes main dwelling and all extensions where present. PV connection to the dwelling's meter must be verified by the presence of a PV generation meter or documentary evidence. In all cases, the PV- generated electricity is included in the assessment of a dwelling only if the dwelling has a PV generation meter serving it. Where it cannot be determined that the PV supply is feeding into a meter serving the dwelling being assessed then no PV should be allocated to that dwelling. Where the PV supply is serving more than one building, or multiple dwellings within the building, the total capacity of the PV is allocated between the buildings on an area weighted basis based on an estimate of the total floor area of all of the buildings or dwellings served by the PV. This applies in all scenarios where the PV supplies more than one building, or multiple dwellings within the building, including where the other buildings are either all dwellings, a mix of dwellings and non- domestic buildings or all non-domestic buildings.

41. Convention 9.11 Transaction type “None of the above” should be avoided where possible; the case below should be treated as follows: o Right to Buy transactions should be recorded as “Non-marketed sale”

42. Convention 3.04  The amendment to this Convention is aimed at ensuring that any obstructions blocking access to loft insulation be treated in the same way that a boarded loft was previously treated  Partly obstructed lofts are treated as follows:  <= 25% obstructed: treat as not obstructed and record thickness of visible insulation  >25 to 75%: divide into extensions  > 75%: treat as fully obstructed “pitched, access, loft insulation unknown”  Remember, a weighted-average is only used where there are various levels of loft insulation. Areas with no loft insulation present should be treated as extensions.  The amendment to this Convention is aimed at ensuring that any obstructions blocking access to loft insulation be treated in the same way that a boarded loft was previously treated  Partly obstructed lofts are treated as follows:  <= 25% obstructed: treat as not obstructed and record thickness of visible insulation  >25 to 75%: divide into extensions  > 75%: treat as fully obstructed “pitched, access, loft insulation unknown”  Remember, a weighted-average is only used where there are various levels of loft insulation. Areas with no loft insulation present should be treated as extensions.

43. Convention 3.08  The changing of default U-values has always been an area of difficulty, and we are pleased that the Conventions group made substantial changes to the evidencing requirements for the inclusion of amended U-values.  DEAs must now provide specific documentary evidence of the thermal conductivity of the individual materials of the building element of the property being assessed is provided and was undertaken in accordance with BR 443 “Conventions for U-value calculations”.  Quidos will now be accepting U-value calculations produced by Level 4-qualified NDEAs.  Where the evidence requirement above cannot be met, DEAs must use the default “as- built” values.  The changing of default U-values has always been an area of difficulty, and we are pleased that the Conventions group made substantial changes to the evidencing requirements for the inclusion of amended U-values.  DEAs must now provide specific documentary evidence of the thermal conductivity of the individual materials of the building element of the property being assessed is provided and was undertaken in accordance with BR 443 “Conventions for U-value calculations”.  Quidos will now be accepting U-value calculations produced by Level 4-qualified NDEAs.  Where the evidence requirement above cannot be met, DEAs must use the default “as- built” values.

44. Convention 3.12  This Convention amendment is likely to be the most welcomed from all DEAs. It allows assessors to make better assumptions as to the manufactured age of double-glazing units.  Where there is no evidence of the manufacturing date of the units on the frame or spacer bar, or in the absence of documentary evidence (FENSA certificate, manufacturers guarantee), the building age can be used as the default.  This convention does not mean that DEAs can stop attempting to collect the correct documentary evidence, but allows a certain amount of flexibility where evidence is unavailable.  This Convention amendment is likely to be the most welcomed from all DEAs. It allows assessors to make better assumptions as to the manufactured age of double-glazing units.  Where there is no evidence of the manufacturing date of the units on the frame or spacer bar, or in the absence of documentary evidence (FENSA certificate, manufacturers guarantee), the building age can be used as the default.  This convention does not mean that DEAs can stop attempting to collect the correct documentary evidence, but allows a certain amount of flexibility where evidence is unavailable.

45. Convention 9.05  A lot of effort has been put into ensuring the approach taken under RdSAP for the provision of Solar PV is mirrored by On-Construction SAP, and Non-domestic EPCs.  The kWh power output should only be input if a valid MCS certificate is provided, or details available from the wiring schematic diagram adjacent to the electricity meter or consumer unit. A roof area percentage must be used in the absence of this.  DEAs must verify the connection of the PV to the dwelling’s electricity meter, either from the PV generation meter or documentary evidence. DEAs must not allocate PV to the dwelling if this cannot be ascertained.  If the PV panels serve more than one building, the total power should be allocated on an floor area-weighed basis.  A lot of effort has been put into ensuring the approach taken under RdSAP for the provision of Solar PV is mirrored by On-Construction SAP, and Non-domestic EPCs.  The kWh power output should only be input if a valid MCS certificate is provided, or details available from the wiring schematic diagram adjacent to the electricity meter or consumer unit. A roof area percentage must be used in the absence of this.  DEAs must verify the connection of the PV to the dwelling’s electricity meter, either from the PV generation meter or documentary evidence. DEAs must not allocate PV to the dwelling if this cannot be ascertained.  If the PV panels serve more than one building, the total power should be allocated on an floor area-weighed basis.

46. Review of amended Conventions  The changes to photovoltaics and glazing age will be the most noticeable change for DEAs. However, assessors are still responsible for the data they collect and evidence they are required to provide. Always make use of your site notes to clarify your choices.  Assessors must familiarise themselves with the amendments in terms of changing U-values. A U-value certificate should not be taken on face value, and reviewed by the DEA to ensure that it was created by somebody confirmed to be able to produce U-values.  The changes to photovoltaics and glazing age will be the most noticeable change for DEAs. However, assessors are still responsible for the data they collect and evidence they are required to provide. Always make use of your site notes to clarify your choices.  Assessors must familiarise themselves with the amendments in terms of changing U-values. A U-value certificate should not be taken on face value, and reviewed by the DEA to ensure that it was created by somebody confirmed to be able to produce U-values.

47. What does this mean for DEAs?

48. So what does this mean for DEAs?  On the face of it, there are a lot of changes made in this new version of the Conventions, but the majority are refined wording or evidencing requirements.  The Conventions should be seen as part of an assessor’s on-site equipment. DEAs should consider bringing a printed copy of them with them to each assessment they undertake to ensure that the correct methodology is undertaken.  On the face of it, there are a lot of changes made in this new version of the Conventions, but the majority are refined wording or evidencing requirements.  The Conventions should be seen as part of an assessor’s on-site equipment. DEAs should consider bringing a printed copy of them with them to each assessment they undertake to ensure that the correct methodology is undertaken.

49. Further information  The new RdSAP Conventions are available to download from iQ-Energy, the Quidos Support Log, and in accessible formats on request.  Should you have any questions about these changes, your first point of contact should be our Support Log; either email support@quidos.co.uk or log your query to http://support.quidos.co.uk  Don’t forget to try the Conventions Quiz in iQ-Energy.  Please remember that these Conventions should be used from 1 st October 2016. The previous release will still be used for lodgements and QA purposes up until that date.  The new RdSAP Conventions are available to download from iQ-Energy, the Quidos Support Log, and in accessible formats on request.  Should you have any questions about these changes, your first point of contact should be our Support Log; either email support@quidos.co.uk or log your query to http://support.quidos.co.uk  Don’t forget to try the Conventions Quiz in iQ-Energy.  Please remember that these Conventions should be used from 1 st October 2016. The previous release will still be used for lodgements and QA purposes up until that date.

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