TrustMark and the Delivery of PAS2035


TrustMark has incorporated the new specification, the requirements for registration of the Retrofit Roles and the agreed transitional arrangements into Annex B of our Framework Operating Requirements, so that going forward, where a consumer engages with a TrustMark Registered Business about the installation of energy efficiency measures, they can have confidence that the work is delivered to improved, recognised specifications and is underpinned by a compliance regime. 

It is important to understand that when a business becomes PAS 2030:2019 certified, then they must adhere to the PAS 2035:2019 requirements for a project, which must be overseen and lodged into the TrustMark Data Warehouse by a TrustMark registered Retrofit Coordinator.

PAS 2035:2019 Retrofit Roles


PAS 2035 specifies the retrofit roles as follows:

  • Retrofit Advisor
  • Retrofit Assessor
  • Retrofit Coordinator
  • Retrofit Designer
  • Retrofit Evaluator

Further information on the retrofit roles and qualifications can be found here. 

Further Resources


If you would like to learn more about why PAS 2035 was created and how it works, visit the following external links:

PAS 2035: An interview with Dr. Peter Rickaby (the technical author of PAS 2035)

The Retrofit Academy

Retrofit Works - Model


PAS 2035:2019 Retrofitting Dwellings for Improved Energy Efficiency


PAS 2035:2019 was sponsored by the UK Government's Department for Business, Energy and Industrial Strategy (BEIS). This is the key document in a framework of new and existing standards on how to conduct effective energy retrofits of existing buildings, it covers how to access dwellings for retrofit, identify improvement options, design and specify Energy Efficiency Measures (EEM) and monitor retrofit projects.

The standard drives the 'whole house approach' including the 'fabric first' methodology. It defines the qualifications and responsibilities of individual retrofit roles and respective activities required prior to and post EEM installation.  It also includes a risk assessment process that builds incrementally robust requirements depending on what requirement path (A, B, or C) the retrofit project is assessed to fall within.

It is not possible to be certified to PAS 2035:2019 in the way that it is with PAS:2030. In the case of PAS 2035:2019. TrustMark Registered Businesses carrying out work within its scope are required to be compliant with its requirements; subject to the transition arrangements outlined below.

PAS 2035 is inextricably linked to PAS 2030:2019, the new industry specification to replace PAS 2030:2017 and is the standard to which all energy efficiency installers must be certified and compliant.

The specifications are available from the BSI Shop.

PAS 2035:2019 - Reduction of Inherent Technical Risk Scores of Energy Efficiency Measures Through the Use of TrustMark Recognised Industry Quality Assurance Schemes


PAS 2035:2019 Annex B Clause B.2 introduces a mechanism that permits the reduction of inherent technical risk scores for a measure(s) where closely defined criteria are met.  Where the intended Retrofit Installer operates under an ‘industry quality assurance scheme’ that has the features as listed in the relevant section of the PAS, a reduction of the inherent technical risk scores by one for the measure(s) covered by that scheme is permitted.  Please see the applicable sections of PAS 2035:2019 for further information.

TrustMark, working closely with our Retrofit Coordinator Scheme Providers and the wider interested parties, has agreed that a consistent approach must be in place so that a TrustMark Registered Retrofit Coordinator considering this provision of the PAS works to a common consistent standard.

Therefore, the following is a list of TrustMark recognised organisations delivering such industry quality assurance schemes as permitted by PAS 2035:2019.  Retrofit Coordinators can recognise these schemes when deciding whether a valid reduction by one can be made to inherent technical risk score for the respective measure(s) within a project.

The list may be added to as further schemes become recognised by TrustMark:

Current Recognised Schemes:

CIGA Guarantee under the quality assurance framework of The IAA

Use online application or website contact details

SWIGA Guarantee

Use online application or website contact details

Should your organisation operate an industry quality assurance scheme as described in PAS 2035:2019 and you require to be considered for TrustMark recognition, you can obtain the published criteria and understand more about the application process for TrustMark recognition by contacting TrustMark directly.

Where the organisation wishes to progress its interest, we will require a formal request, supported by comprehensive and auditable evidence to meet the recognition criteria.

Energy Efficiency Measures for Older and Traditional Buildings: 2-day Course - Level 3 Award Qualification


This qualification is a way of meeting part of the requirements for Retrofit Assessors working under PAS 2035:2019 in respect of some building type categories (please see PAS 2035:2019 for further information). This course is about the energy efficiency and retrofit of traditional buildings, classified as those with the construction of solid brick or stone external walls or pre 1919 timber-framed external walls with any infill, which make up about 35% of UK building stock.

It is delivered by retrofit expert Professor John Edwards, a member of the BSI Retrofit Standards Task Group and the lead author of BS7913: 2013, the British Standard for traditional and historic buildings; also a member of the Steering Groups for PAS2030:2019 and PAS2035:2019.

At the end of this course, participants will increase their familiarity with issues concerning traditional buildings and understand their retrofit requirements more readily.

The course is available for individuals to book a place and for in house group bookings for which there is a substantial discount offered - click here for further details.